Merge pull request 'fix(reconcile): fill earliest month deficit first in multi-month allocations' (#35 ) from fix/fill-first-multi-month-allocation into main

Reviewed-on: #35
fix(reconcile): fill earliest month deficit first in multi-month allocations
2026-05-11 22:01:36 +00:00 · 2026-05-11 23:59:36 +02:00 · 2026-05-11 22:56:49 +02:00 · 2026-05-08 14:56:57 +02:00 · 2026-05-08 12:54:23 +00:00 · 2026-05-08 12:54:16 +00:00
38 changed files with 2846 additions and 206 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,64 @@
 # Changelog
 ## 2026-05-11 23:58 CEST — fix(reconcile): fill earliest month deficit first in multi-month allocations
 - Multi-month payment allocation now fills the earliest in-window deficit first and spills
  any remainder to later months, accounting for prior transactions' contributions to each month.
  Previously a single transaction was split proportionally to each month's total expected fee,
  ignoring what earlier transactions had already paid — surfaced by Matyáš Thér's 200+550 case
  showing 566/183 instead of 500/250.
 - Files: `scripts/match_payments.py`, `go/internal/domain/reconcile/reconcile.go`, tests, parity fixtures.
 ## 2026-05-11 22:56 CEST — fix(python): parse Fio 2-digit-year dates + add `make sync-debug` dry-run tool
 - Fix: `scripts/fio_utils.py` `parse_czech_date` now accepts `DD.MM.YY` / `D.M.YY` in addition to the 4-digit-year variants. Fio's transparent page now mixes both forms in the same response; the 2-digit rows were being silently dropped, which caused `make sync-2026` to miss every recent transfer. Mirrors the Go-side fix from 2026-05-07 (CHANGELOG entry below).
 - Added `--dry-run` and `--print-fio-table` flags to `scripts/sync_fio_to_sheets.py`, plus a `make sync-debug [DAYS=N]` Makefile target. Mirrors `make go-sync-debug`: fetches from Fio and dedupes against the sheet, prints `STATUS=NEW/DUP` per transaction, and prints per-row `Dry run: would append …` lines + `would sort by date` instead of touching the sheet.
 - Added always-on stderr diagnostics in `scripts/fio_utils.py`: which fetcher was selected (authenticated API vs. transparent-page scraper with `FIO_API_TOKEN`-unset warning), and raw-vs-after-filter transaction counts on both paths — so this class of "scraper drops everything" bug surfaces immediately.
 ## 2026-05-08 14:55 CEST — feat(go): M6.6.1 — Pay-button QR popup modal
 - Restored the Python `showPayQR` in-page modal UX that was lost in M6.6 (Pay buttons were navigating the tab to the raw `/qr` PNG).
 - Replaced `<a href="{{qrHref ...}}">Pay</a>` with `<button data-name|amount|month|raw-month>` on `/adults` and `/juniors`; click is handled by a new `static/js/payment-qr.js` IIFE module that opens `#qrModal` with title, account, amount, message, and the QR image.
 - Added `#qrModal` markup to both templates; CSS `display:none` / `.active{display:flex}` rules added (content rules were already present from M6.1). `Esc`, `[close]`, and outside-click all dismiss; coexists with the M6.5 member-detail modal.
 - Removed the now-dead `qrHref` / `qrHrefAll` template helpers from `render.go`.
 - Markup tests in `html_handler_test.go` assert modal IDs, script tag, `data-bank-account`, and that no bare `href="/qr"` links remain.
 - Key files: `go/internal/web/static/js/payment-qr.js`, `go/internal/web/templates/adults.tmpl`, `go/internal/web/templates/juniors.tmpl`, `go/internal/web/render.go`, `go/internal/web/static/css/app.css`.
 ## 2026-05-08 13:57 CEST — feat(go): M6.6 — /qr, /sync-bank, /flush-cache, /version
 - Added `GET /qr`: generates Czech QR Platba PNG from SPD payload (account, amount, message query params); ports Python's `qr_code()` handler exactly including account validation, amount clamping, and `*` stripping.
 - Implemented `GET /sync-bank`: runs Fio sync → infer payments → cache flush, captures output into `sync.tmpl` page with success/error banner.
 - Implemented `GET /flush-cache` + `POST /flush-cache`: form + action that deletes cache files and shows deleted count.
 - Added `GET /version` as a JSON alias of `GET /api/version` (Python parity).
 - Added `FlushCache() (int, error)` to `membership.Sources` interface; implemented on `realSources` via `cache.FileCache.Flush()`.
 - Introduced `web.ActionHandlers{BankSync}` — closure-based dep injection for sync, constructed in `serverCmd` with fio + sheets clients.
 - New dependency: `github.com/skip2/go-qrcode`.
 - Key files: `go/internal/web/qr.go`, `go/internal/web/html_handler.go`, `go/internal/web/server.go`, `go/internal/services/membership/loader.go`, `go/internal/web/templates/sync.tmpl`, `go/internal/web/templates/flush_cache.tmpl`.
 ## 2026-05-08 13:19 CEST — feat(go): M6.5 — member-detail modal JS module
 - Added `static/js/member-detail.js`: fetches `/api/adults` or `/api/juniors` once on page load, caches the response, renders a per-member detail modal on `[i]` row click.
 - Modal sections: status-per-month table, fee exceptions, other transactions, matched payment history, toggleable raw-payments debug view.
 - Keyboard nav: `Esc` closes, `↑`/`↓` walk visible (name-filtered) rows; click outside modal content closes it.
 - Added `[i]` info icon and `#memberModal` markup to `adults.tmpl` and `juniors.tmpl`; all CSS was already in place from M6.1.
 - Added `TestModalMarkup` assertions to `html_handler_test.go`.
 ## 2026-05-08 12:48 CEST — feat(go): M6.4 — Go-native /payments page
 - Extracted `AssemblePayments(ctx)` from the inlined JSON handler body, following the M6.2/M6.3 `AssembleAdults`/`AssembleJuniors` pattern.
 - Added `PaymentsPageData` to `render.go`; wired `HTMLHandler.ServePayments` to call `AssemblePayments` and render the new template.
 - Replaced the "Coming in M6.4" placeholder in `payments.tmpl` with the full grouped-by-person ledger: alphabetical `<h2>` member blocks, each with a `txn-table` (Date / Amount / Purpose / Bank Message), newest-first rows, `"Unmatched / Unknown"` bucket.
 - Appended ledger CSS classes to `app.css` (`.ledger-container`, `.member-block`, `.txn-table`, `.txn-{date,amount,purpose,message}`, `tr:hover`).
 - Added `TestPaymentsPage` markup test. No filters, no JS — matches the Python page.
 ## 2026-05-08 11:25 CEST — feat(go): M6.3 — Go-native /juniors page
 - Extracted `AssembleJuniors(ctx)` from the JSON handler so HTML and JSON share one view-model path (mirrors `AssembleAdults`).
 - Added `JuniorsPageData` to `render.go`; wired `HTMLHandler.ServeJuniors` to call `AssembleJuniors` and render the new template.
 - Replaced the 4-line "Coming in M6.3" placeholder in `juniors.tmpl` with the full template: member table, name/month-range filters, totals row, Credits + Debts sections, Pay / Pay All links to `/qr`. No Unmatched section (parity with Python).
 - J/A attendance breakdown and `"?"` sentinel rendered via `MonthCell.Text` produced by `buildJuniorMemberRow` — no extra template logic.
 - `make parity` reports 3/3 routes OK; all Go tests pass.
 ## 2026-05-08 11:11 CEST — fix: period selector showed only Dec 2025+ on adults
 - Restored the `2025-09 → 2025-10` adult merge in `scripts/attendance.py` and `go/internal/services/membership/sources.go` (commented-out by `1257f0d`); the `2025-12 → 2026-01` mapping stays disabled per product decision (Dec and Jan are billed separately for adults).
--- a/4
+++ b/4
@@ -35,6 +35,7 @@ help:
 	@echo "  make sync        - Sync Fio transactions to Google Sheets"
 	@echo "  make sync-2025   - Sync Fio transactions for Q4 2025 (Oct-Dec)"
 	@echo "  make sync-2026   - Sync Fio transactions for the whole year of 2026"
 	@echo "  make sync-debug [DAYS=N] - Dry-run Python sync with Fio diagnostics and txn table (default DAYS=30)"
 	@echo "  make infer       - Infer payment details (Person, Purpose, Amount) in the sheet"
 	@echo "  make reconcile   - Show balance report using Google Sheets data"
 	@echo "  make venv        - Sync virtual environment with pyproject.toml"
@@ -125,6 +126,9 @@ sync-2025: $(PYTHON)
 sync-2026: $(PYTHON)
 	$(PYTHON) scripts/sync_fio_to_sheets.py --credentials .secret/fuj-management-bot-credentials.json --from 2026-01-01 --to 2026-12-31 --sort-by-date
 sync-debug: $(PYTHON)  ## Dry-run Python sync with Fio diagnostics and txn table (default DAYS=30)
 	$(PYTHON) scripts/sync_fio_to_sheets.py --credentials .secret/fuj-management-bot-credentials.json --days $(DAYS) --dry-run --print-fio-table
 infer: $(PYTHON)
 	$(PYTHON) scripts/infer_payments.py --credentials $(CREDENTIALS)
--- a/docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md
+++ b/docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md
@@ -4,7 +4,7 @@ Companion to [2026-05-03-2349-go-backend-rewrite.md](2026-05-03-2349-go-backend-
 **Current milestone:** M6 — Go-native HTML frontend
 **Started:** 2026-05-04
-**Last updated:** 2026-05-08 (M6.2 merged)
+**Last updated:** 2026-05-08 (M6.6 + M6.6.1 merged)
 ## How to use
@@ -112,10 +112,11 @@ Goal: feature-equivalent UX on the Go side, designed cleanly. Not a Jinja port.
 - [x] **M6.1** Template skeleton: base layout, nav (Adults/Juniors/Payments/Sync/Flush), terminal-green-on-black theme; `embed.FS` for `templates/` + `static/` — `78e5059`
 - [x] **M6.2** `/adults` page: table, name filter input, month range filter, totals row, credits/debts/unmatched sections, Pay buttons that link to `/qr` — `c85748b`
- [ ] **M6.3** `/juniors` page: same structure + per-month J/A attendance breakdown + `"?"` sentinel rendering
+- [x] **M6.3** `/juniors` page: same structure + per-month J/A attendance breakdown + `"?"` sentinel rendering — `9564103`
- [ ] **M6.4** `/payments` page: grouped-by-person ledger view
+- [x] **M6.4** `/payments` page: grouped-by-person ledger view — `689f1c0`
- [ ] **M6.5** Modal JS module (`static/js/member-detail.js`): fetches `/api/adults` (or juniors), renders status/exceptions/transactions on row click; keyboard nav (Esc, ↑/↓)
+- [x] **M6.5** Modal JS module (`static/js/member-detail.js`): fetches `/api/adults` (or juniors), renders status/exceptions/transactions on row click; keyboard nav (Esc, ↑/↓) — `e53e238`
- [ ] **M6.6** `/qr`, `/sync-bank`, `/flush-cache`, `/version` pages
+- [x] **M6.6** `/qr`, `/sync-bank`, `/flush-cache`, `/version` pages — `f6ba85b`
 - [x] **M6.6.1** Pay-button QR popup modal (`payment-qr.js`); restores Python `showPayQR` UX lost in M6.6 — `4276d7b`
 - [ ] **M6.7** Wire `embed.FS` into handlers; verify single-binary deployment includes all assets
 **Gate:** Browser smoke on :8080: all pages render, name+month filters work, modal opens with correct data, QR loads, sync/flush work end-to-end.
--- a/docs/plans/2026-05-08-1123-go-m6-3-juniors-page.md
+++ b/docs/plans/2026-05-08-1123-go-m6-3-juniors-page.md
@@ -0,0 +1,67 @@
 # M6.3 — Go-native `/juniors` page
 ## Context
 The Go rewrite is in milestone M6 (Go-native HTML frontend). M6.2 shipped the `/adults` page in commit `c85748b`; the [progress tracker](../../srv/personal/fuj-management/docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md) line 115 names M6.3 as:
 > `/juniors` page: same structure + per-month J/A attendance breakdown + `"?"` sentinel rendering
 The Go side already has `buildJuniorsResponse` (M5.2) that produces the full JSON view model, and the JuniorsResponse uses the same `MemberRow`/`MonthCell`/`TotalCell` types as `AdultsResponse`. Critically, `buildJuniorMemberRow` ([go/internal/web/api/build_juniors.go:142](../../srv/personal/fuj-management/go/internal/web/api/build_juniors.go#L142)) already bakes the J/A breakdown (e.g. `"3/500 CZK (4:2J,2A)"`) and the `"?"` sentinel into `MonthCell.Text` — no template-level junior-specific logic is required for the M6.3 table.
 Today `juniors.tmpl` is a 4-line "Coming in M6.3" placeholder and `HTMLHandler.ServeJuniors` ([html_handler.go:35](../../srv/personal/fuj-management/go/internal/web/html_handler.go#L35)) just renders that placeholder. Goal of M6.3: produce a working `/juniors` page that mirrors the structure of `/adults` and reaches feature parity with the Python `/juniors` route.
 ## Approach
 Mirror the M6.2 pattern exactly:
 1. **Extract `AssembleJuniors(ctx)`** from the JSON handler so HTML + JSON share one view-model assembly path (the parity contract).
 2. **Add `JuniorsPageData`** wrapper type next to `AdultsPageData` in `render.go`.
 3. **Replace `juniors.tmpl`** with an adults-shaped layout. Because `JuniorsResponse` shares the same field names used by `adults.tmpl` (`Months`, `RawMonths`, `Results`, `Totals`, `Credits`, `Debts`, `AttendanceURL`, `PaymentsURL`, `BankAccount`, `CurrentMonth`), the template body is essentially copy/paste with one parity tweak (see "Decisions" below).
 4. **Wire `HTMLHandler.ServeJuniors`** to call `AssembleJuniors` and render the new template, parallel to `ServeAdults`.
 No new CSS, no new JS — `filters.js` and the `cell-*` classes (lifted in M6.1) already cover juniors.
 ## Files to modify
 | File | Change |
 | --- | --- |
 | [go/internal/web/api/handler.go](../../srv/personal/fuj-management/go/internal/web/api/handler.go) | Add `AssembleJuniors(ctx) (JuniorsResponse, error)`; refactor existing `ServeJuniors` to call it (mirrors `AssembleAdults` at line 47). |
 | [go/internal/web/render.go](../../srv/personal/fuj-management/go/internal/web/render.go) | Add `JuniorsPageData` struct (PageData + `Data api.JuniorsResponse` + `Error string`). |
 | [go/internal/web/html_handler.go](../../srv/personal/fuj-management/go/internal/web/html_handler.go) | Replace stub `ServeJuniors` with the same shape as `ServeAdults` (lines 20–33). |
 | [go/internal/web/templates/juniors.tmpl](../../srv/personal/fuj-management/go/internal/web/templates/juniors.tmpl) | Replace placeholder with a structurally identical copy of [adults.tmpl](../../srv/personal/fuj-management/go/internal/web/templates/adults.tmpl), with the title swapped to "Juniors Dashboard" and the Unmatched section removed (parity with Python). |
 | [docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md](../../srv/personal/fuj-management/docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md) | Tick `M6.3` once merged, append merge SHA. |
 | [CHANGELOG.md](../../srv/personal/fuj-management/CHANGELOG.md) | New top-most entry per CLAUDE.md format. |
 ## Decisions captured
 - **No "Unmatched Transactions" section on `/juniors`.** Python's [templates/juniors.html](../../srv/personal/fuj-management/templates/juniors.html) renders only Credits + Debts (no Unmatched block). Although `JuniorsResponse.Unmatched` is populated, parity says we don't render it on juniors. The data stays available for the modal in M6.5.
 - **Reuse `qrHref` / `qrHrefAll` template funcs** from [render.go:35–57](../../srv/personal/fuj-management/go/internal/web/render.go#L35-L57). They are name-only (not adult-specific) and already on `tmplFuncs`.
 - **Reuse the existing `cell-empty / cell-unpaid / cell-unpaid-current / cell-ok / cell-overridden` cell-class branching** from `adults.tmpl` lines 60–67 verbatim. The "?" sentinel is rendered as plain `{{$cell.Text}}` text — no template branch needed because `buildJuniorMemberRow` produces `"?"` or `"? CZK"` already.
 - **No template helper extraction** (e.g. shared `_table_section.tmpl`). The two templates will be near-duplicates, but extracting a shared partial now is premature — wait until M6.4 or later when patterns settle. M6.2 didn't extract one either.
 - **Branch**: `feat/go-m6-3-juniors-page`, MR via `tea pr create` per CLAUDE.md.
 ## Verification
 End-to-end smoke (parallel-running both backends as in M5/M6.2):
 1. `cd go && make run` (or whatever target boots the Go server on :8080).
 2. Browser-load `http://localhost:8080/juniors`. Confirm:
   - Member rows render with cells containing fee + attendance breakdown like `0/500 CZK (3:2J,1A)`.
   - At least one `"?"` cell visible (any junior with exactly one session in some month).
   - Filter input narrows rows by name; From/To month selects hide columns via `data-month-idx`.
   - `Pay` button visible on past-month unpaid cells; clicking links to `/qr?...`. (The QR endpoint itself lands in M6.6 — only the link target is in scope here.)
   - `Pay All` visible on rows with `Balance < 0`.
   - TOTAL row sums correctly per month.
   - Credits + Debts sections render when present; no Unmatched section.
 3. JSON parity: `make parity` against the M3 fixture corpus must still report zero non-allowlisted diffs for `/api/juniors` (the `AssembleJuniors` extraction must not change wire output).
 4. Compare side-by-side against Python `/juniors` on :5001 for the same fixture; the table cells should match cell-for-cell modulo the known M5 allowlist.
 ## Out of scope
 - Modal (`[i]` info button + `#memberModal`) — that is M6.5.
 - QR endpoint, `/sync-bank`, `/flush-cache`, `/version` pages — M6.6.
 - Embed.FS deploy verification — M6.7.
 ## Plan-file relocation
 Per [CLAUDE.md](../../srv/personal/fuj-management/CLAUDE.md) "Plans" section, plan files belong in `docs/plans/YYYY-MM-DD-HHMM-<slug>.md` inside the repo. Plan mode forced this draft into `~/.claude/plans/`; first step after ExitPlanMode is to copy this file to `docs/plans/2026-05-08-HHMM-go-m6-3-juniors-page.md` (resolving the timestamp at that moment) and commit it on the feature branch alongside the implementation.
--- a/docs/plans/2026-05-08-1220-go-m6-4-payments-page.md
+++ b/docs/plans/2026-05-08-1220-go-m6-4-payments-page.md
@@ -0,0 +1,215 @@
 # M6.4 — Go-native `/payments` page (grouped-by-person ledger)
 > Plan-mode note: per project convention this plan should live at
 > `docs/plans/2026-05-08-1220-go-m6-4-payments-page.md`. The first execution
 > step after approval is to copy this file there.
 ## Context
 The Go port of the Flask app is at milestone **M6.4**: replace the placeholder
 `/payments` template ([go/internal/web/templates/payments.tmpl](go/internal/web/templates/payments.tmpl))
 with a feature-equivalent grouped-by-person ledger view, matching the Python
 [templates/payments.html](templates/payments.html) page.
 Compared to M6.2 (`/adults`) and M6.3 (`/juniors`), this page is **structurally
 much simpler**:
 - No filters (no name input, no month-range selects).
 - No totals / credits / debts / unmatched-as-extra-section.
 - No JS (no `filters.js`, no modal — modal is M6.5 territory and Python's
  payments page itself has none).
 - No QR / Pay buttons.
 - Single grouping dimension: **by person**, sorted alphabetically, with a
  synthetic `"Unmatched / Unknown"` bucket appended.
 - Each person's transactions sorted **newest-first**.
 - Columns: Date, Amount (right-aligned, green), Purpose, Bank Message.
 The JSON API side is already done (`/api/payments` at
 [go/internal/web/api/handler.go:78-86](go/internal/web/api/handler.go#L78-L86)),
 returning a `PaymentsResponse{ GroupedPayments, SortedPeople, AttendanceURL,
 PaymentsURL }`. The HTML side just needs to consume it.
 ## Approach
 Mirror the M6.2/M6.3 pattern: extract an `AssembleX(ctx)` method, add a typed
 `PageData` wrapper, render a real template, lift the page-specific CSS into the
 shared stylesheet.
 ### 1. Extract `AssemblePayments(ctx) (PaymentsResponse, error)`
 In [go/internal/web/api/handler.go](go/internal/web/api/handler.go), refactor
 `ServePayments` (currently inlines the load+build at lines 78-86) to mirror
 `AssembleAdults` / `AssembleJuniors`:
 ```go
 func (h *Handler) ServePayments(w http.ResponseWriter, r *http.Request) {
    resp, err := h.AssemblePayments(r.Context())
    if err != nil { h.writeError(w, r, err); return }
    writeJSON(w, resp)
 }
 func (h *Handler) AssemblePayments(ctx context.Context) (PaymentsResponse, error) {
    txns, err := h.Sources.LoadTransactions(ctx)
    if err != nil { return PaymentsResponse{}, fmt.Errorf("load transactions: %w", err) }
    return buildPaymentsResponse(txns, h.allMemberNames(ctx)), nil
 }
 ```
 Pure refactor — `make parity` should report zero diffs on `/api/payments`.
 ### 2. Add `PaymentsPageData` wrapper
 In [go/internal/web/render.go](go/internal/web/render.go), alongside
 `AdultsPageData` / `JuniorsPageData`:
 ```go
 type PaymentsPageData struct {
    PageData
    Data  api.PaymentsResponse
    Error string
 }
 ```
 No changes needed to `pageNames` — `"payments"` is already registered.
 ### 3. Rewire HTML handler
 Replace [go/internal/web/html_handler.go:50-52](go/internal/web/html_handler.go#L50-L52):
 ```go
 func (h *HTMLHandler) ServePayments(w http.ResponseWriter, r *http.Request) {
    data := PaymentsPageData{ PageData: PageData{Active: "payments", Build: h.build} }
    resp, err := h.apiHandler.AssemblePayments(r.Context())
    if err != nil { data.Error = err.Error() } else { data.Data = resp }
    h.renderer.Render(w, "payments", data)
 }
 ```
 ### 4. Replace template stub
 Rewrite [go/internal/web/templates/payments.tmpl](go/internal/web/templates/payments.tmpl)
 (currently a 5-line placeholder). Structure:
 ```gotmpl
 {{define "title"}}Payments Ledger{{end}}
 {{define "content"}}
 <h1>Payments Ledger</h1>
 <p class="description">
  All bank transactions from the
  <a href="{{.Data.PaymentsURL}}" target="_blank">payments sheet</a>,
  grouped by member. Names are matched against the
  <a href="{{.Data.AttendanceURL}}" target="_blank">attendance sheet</a>.
 </p>
 {{if .Error}}<p class="error">{{.Error}}</p>{{end}}
 <div class="ledger-container">
 {{range $person := .Data.SortedPeople}}
  <div class="member-block">
    <h2>{{$person}}</h2>
    <table class="txn-table">
      <thead><tr>
        <th class="txn-date">Date</th>
        <th class="txn-amount">Amount</th>
        <th class="txn-purpose">Purpose</th>
        <th class="txn-message">Bank Message</th>
      </tr></thead>
      <tbody>
      {{range $tx := index $.Data.GroupedPayments $person}}
        <tr>
          <td class="txn-date">{{$tx.Date}}</td>
          <td class="txn-amount">{{printf "%.0f" $tx.Amount}} CZK</td>
          <td class="txn-purpose">{{$tx.Purpose}}</td>
          <td class="txn-message">{{$tx.Message}}</td>
        </tr>
      {{end}}
      </tbody>
    </table>
  </div>
 {{end}}
 </div>
 {{end}}
 ```
 Notes:
 - `printf "%.0f"` matches the visual style of integer CZK amounts (Python prints
  the float as-is, but bank-row amounts are always whole CZK). If the user
  prefers exact Python parity (`750.0 CZK`), drop the `printf` and use
  `{{$tx.Amount}}`.
 - Iterating a `map` requires using `.Data.SortedPeople` to drive order then
  `index $.Data.GroupedPayments $person` — Go templates don't preserve map
  insertion order.
 ### 5. Add CSS classes to `app.css`
 Append the page-specific rules from [templates/payments.html:111-164](templates/payments.html#L111-L164)
 to [go/internal/web/static/css/app.css](go/internal/web/static/css/app.css):
 `.ledger-container`, `.member-block`, `.txn-table`, `.txn-table th/td`,
 `.txn-date`, `.txn-amount`, `.txn-purpose`, `.txn-message`, `tr:hover`. The
 terminal-green palette already matches.
 ### 6. Unit test
 Add a markup-level test to `go/internal/web/html_handler_test.go` (the file
 created in M6.2/M6.3) following the same pattern: stub `Sources` returning a
 fixed transaction list, assert response is HTML 200, assert key strings appear
 (person names as `<h2>`, "Payments Ledger" `<h1>`, expected amount, "Unmatched
 / Unknown" bucket when an unattributed tx exists).
 ## Critical files
 | Action  | Path |
 |---------|------|
 | edit    | [go/internal/web/api/handler.go](go/internal/web/api/handler.go) — extract `AssemblePayments` |
 | edit    | [go/internal/web/render.go](go/internal/web/render.go) — add `PaymentsPageData` |
 | edit    | [go/internal/web/html_handler.go](go/internal/web/html_handler.go) — rewire `ServePayments` |
 | rewrite | [go/internal/web/templates/payments.tmpl](go/internal/web/templates/payments.tmpl) — real template |
 | edit    | [go/internal/web/static/css/app.css](go/internal/web/static/css/app.css) — append ledger CSS |
 | edit    | `go/internal/web/html_handler_test.go` — payments markup test |
 No changes to `server.go`, `assets.go`, `Sources` interface, `buildPaymentsResponse`,
 or any domain code — these were completed in M5 / M6.1.
 ## Reused existing helpers
 - [go/internal/web/api/build_payments.go](go/internal/web/api/build_payments.go) — `buildPaymentsResponse` (existing, unchanged)
 - [go/internal/web/api/build_common.go:84-117](go/internal/web/api/build_common.go#L84-L117) — `groupRawPaymentsByPerson` handles canonicalization, comma-splitting, `[?]` stripping, newest-first sort
 - [go/internal/web/api/handler.go:116-129](go/internal/web/api/handler.go#L116-L129) — `allMemberNames`
 - [go/internal/web/templates/partials/nav.tmpl](go/internal/web/templates/partials/nav.tmpl) and `footer.tmpl` — already include the `[Payments Ledger]` nav link
 ## Verification
 End-to-end:
 1. `cd go && make go-build go-test go-lint` — all green.
 2. `make parity` — confirm the `AssemblePayments` extraction is byte-equal on
   `/api/payments`.
 3. `make web-go &` then:
   - `curl -i localhost:8080/payments | head -30` — HTTP 200, `text/html`.
   - Browser load `http://localhost:8080/payments`:
     - "Payments Ledger" heading + description with two clickable sheet links.
     - Alphabetical member blocks, each with a table.
     - Amounts right-aligned, green, "CZK" suffix.
     - Newest-first ordering inside each block.
     - "Unmatched / Unknown" bucket sorts in alphabetical position (capital U →
       near end).
     - Hover on a row darkens the background.
     - Nav highlights `[Payments Ledger]` as the active link.
   - Cross-check with Python: `make web-py &` → `http://localhost:5001/payments`
     should look visually identical except for nav styling.
 4. `make web-py & make web-go &` then `tea pr create` once committed (per
   project branch-per-feature workflow).
 ## Branching
 Create `feat/go-m6-4-payments-page` off `main`, push, open MR via `tea`.
 Follow project conventions: Co-Authored-By trailer, CHANGELOG entry once user
 confirms it works, tick **M6.4** in
 [docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md:116](docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md#L116)
 with the merge SHA after the user merges in Gitea.
 ## Out of scope (deferred)
 - **Modal / `[i]` info button** — M6.5 (not present in Python `/payments` either).
 - **Period selector** — `/payments` has none in Python; not adding one.
 - **embed.FS deploy verification** — M6.7.
 - **Shared partial extraction** — payments structurally diverges from
  adults/juniors enough that there's no obvious common partial to lift; defer.
--- a/docs/plans/2026-05-08-1259-go-m6-5-modal-js.md
+++ b/docs/plans/2026-05-08-1259-go-m6-5-modal-js.md
@@ -0,0 +1,288 @@
 # M6.5 — Member-detail modal JS module (`/adults`, `/juniors`)
 > Plan-mode note: per project convention this plan should live at
 > `docs/plans/2026-05-08-HHMM-go-m6-5-modal-js.md` (use `date "+%Y-%m-%d-%H%M"`
 > when copying). The first execution step after approval is to copy this file
 > there. Branch: `feat/go-m6-5-modal-js` off `main`.
 ## Context
 The Go port of the Flask app is at milestone **M6.5**: the `/adults` and
 `/juniors` pages currently render their tables ([go/internal/web/templates/adults.tmpl](go/internal/web/templates/adults.tmpl),
 [go/internal/web/templates/juniors.tmpl](go/internal/web/templates/juniors.tmpl))
 but have no row-click member-detail modal — the feature that lets a user click
 a member's row to inspect status per month, exception overrides, "other"
 transactions, the matched payment list, and a debug raw-payments view.
 The Python implementation lives inline in
 [templates/adults.html:718-993](templates/adults.html#L718-L993)
 (matching code in [templates/juniors.html](templates/juniors.html) — same
 modal markup and JS). It uses globals injected via Jinja:
 `memberData`, `sortedMonths`, `monthLabels`, `rawPaymentsByPerson`. M6.5
 replaces this with a clean static JS module.
 Per milestone wording — *"fetches `/api/adults` (or juniors), renders
 status/exceptions/transactions on row click; keyboard nav (Esc, ↑/↓)"* —
 and per the user's design choice: the JS module fetches `/api/<page>` **once
 on page load** and caches the response in a module-scoped variable. Subsequent
 row clicks render synchronously from cache. This keeps HTML purely
 server-rendered and reuses the parity-tested JSON contract already shipped in
 M5.
 All the building blocks are already in place:
 - **JSON API**: `/api/adults` and `/api/juniors` already return
  `member_data`, `month_labels`, `raw_payments` as nested objects (see
  [go/internal/web/api/adults.go:27-42](go/internal/web/api/adults.go#L27-L42)
  and the analogous juniors response). Junior `Expected` serialises as `"?"`
  for the unknown sentinel via custom `MarshalJSON`
  ([go/internal/web/api/types.go:24-29](go/internal/web/api/types.go#L24-L29)) — JS sees a literal string `"?"`.
 - **CSS**: `#memberModal`, `.modal-content`, `.modal-section`, `.modal-table`,
  `.tx-list`, `.tx-item`, `.tx-meta`, `.tx-amount`, `.info-icon`, `.raw-toggle`
  were lifted whole during M6.1 and live in
  [go/internal/web/static/css/app.css](go/internal/web/static/css/app.css)
  (lines 168-487). No CSS work needed.
 - **Member-row hooks**: `tr.member-row[data-name="..."]` and `td.member-name`
  are already rendered by both templates.
 - **JS module convention**: `static/js/filters.js` is loaded with `<script src="/static/js/filters.js" defer>`;
  M6.5 adds a sibling `static/js/member-detail.js` with the same loading
  pattern.
 ## Approach
 ### 1. Add `[i]` info icon + `#memberModal` markup to both templates
 In [go/internal/web/templates/adults.tmpl](go/internal/web/templates/adults.tmpl)
 and [go/internal/web/templates/juniors.tmpl](go/internal/web/templates/juniors.tmpl):
 a. Inside the `<td class="member-name">{{$row.Name}}</td>` cell (line 59 of
   each template), append the icon button:
   ```gotmpl
   <td class="member-name">{{$row.Name}}<span class="info-icon" data-name="{{$row.Name}}" title="Show details">[i]</span></td>
   ```
   Using a `data-name` attribute and a CSS class (rather than `onclick="..."`)
   keeps the template free of inline JS — the module wires up the listener
   itself.
 b. After the closing `</div>` of the table-container / sections, before the
   `<script>` tag at line 140 (adults) / 120 (juniors), inject the modal
   markup. Mirror the Python structure verbatim
   ([templates/adults.html:644-707](templates/adults.html#L644-L707)):
   ```gotmpl
   <div id="memberModal" class="modal" onclick="if (event.target === this) this.classList.remove('active')">
     <div class="modal-content">
       <div class="modal-header">
         <span class="modal-title" id="modalMemberName">—</span>
         <span id="modalTier" class="modal-tier"></span>
         <a href="#" class="modal-close" onclick="event.preventDefault(); document.getElementById('memberModal').classList.remove('active')">[x]</a>
       </div>
       <div class="modal-section">
         <div class="modal-section-title">Status by Month</div>
         <table class="modal-table">
           <thead><tr><th>Month</th><th>Sessions</th><th>Expected</th><th>Paid</th><th>Status</th></tr></thead>
           <tbody id="modalStatusBody"></tbody>
         </table>
       </div>
       <div class="modal-section" id="modalExceptionSection" style="display:none">
         <div class="modal-section-title">Exception Overrides</div>
         <div id="modalExceptionList" class="tx-list"></div>
       </div>
       <div class="modal-section" id="modalOtherSection" style="display:none">
         <div class="modal-section-title">Other Payments</div>
         <div id="modalOtherList" class="tx-list"></div>
       </div>
       <div class="modal-section">
         <div class="modal-section-title">Matched Transactions</div>
         <div id="modalTxList" class="tx-list"></div>
       </div>
       <div class="modal-section">
         <div class="modal-section-title">
           Raw Payments (debug)
           <a href="#" id="rawPaymentsToggle" class="raw-toggle">[show]</a>
         </div>
         <div id="modalRawList" class="tx-list" style="display:none"></div>
       </div>
     </div>
   </div>
   ```
 c. Add the script tag alongside `filters.js`. To tell the module which API
   endpoint to fetch, use a `data-page` attribute on `body` (or on the
   filter container — already exists). Simplest: add `data-page="adults"` /
   `data-page="juniors"` to the existing `<div id="filterContainer">`.
   The module reads it on load.
   ```gotmpl
   <script src="/static/js/member-detail.js" defer></script>
   ```
 ### 2. Create [go/internal/web/static/js/member-detail.js](go/internal/web/static/js/member-detail.js)
 A single shared module — both pages use the same DOM contract, so the same
 JS works for both. Structure (vanilla ES, no build step, matches `filters.js`
 style — IIFE, `'use strict'`, no globals leaked):
 ```js
 (function () {
  'use strict';
  const container = document.getElementById('filterContainer');
  if (!container) return;
  const page = container.dataset.page;        // "adults" | "juniors"
  if (!page) return;
  let apiData = null;          // cached /api/<page> response
  let currentMemberName = null;
  // ── Data load ─────────────────────────────────────────────────────────
  async function loadData() {
    if (apiData) return apiData;
    const r = await fetch('/api/' + page);
    if (!r.ok) throw new Error('failed to fetch /api/' + page);
    apiData = await r.json();
    return apiData;
  }
  // Pre-warm immediately so first click is instant.
  loadData().catch(err => console.error('[member-detail]', err));
  // ── Modal render ──────────────────────────────────────────────────────
  async function showMember(name) { /* port of Python showMemberDetails */ }
  function toggleRawPayments(ev)  { /* port */ }
  function closeModal()           { document.getElementById('memberModal').classList.remove('active'); }
  function navigateMember(dir)    { /* port — walk visible .member-row */ }
  // ── Wiring ────────────────────────────────────────────────────────────
  document.querySelectorAll('.info-icon[data-name]').forEach(el => {
    el.addEventListener('click', ev => {
      ev.stopPropagation();
      showMember(el.dataset.name);
    });
  });
  document.getElementById('rawPaymentsToggle').addEventListener('click', toggleRawPayments);
  document.addEventListener('keydown', e => {
    const modal = document.getElementById('memberModal');
    if (e.key === 'Escape') { closeModal(); return; }
    if (!modal.classList.contains('active')) return;
    if (e.key === 'ArrowDown') { e.preventDefault(); navigateMember(1); }
    if (e.key === 'ArrowUp')   { e.preventDefault(); navigateMember(-1); }
  });
 }());
 ```
 The four `port` functions transcribe Python literally, with two adjustments:
 - `data.tier` — read directly from the API response (already present as
  `AdultsMemberData.Tier` / `JuniorsMemberData.Tier`).
 - Junior `expected` may equal the literal string `"?"` (sentinel from
  `Expected.MarshalJSON`). The status-row formatter must treat string
  `expected` as "unknown / single attendance" and skip the numeric
  comparisons — same logic Python uses when it sees `"?"`.
 `navigateMember` walks `document.querySelectorAll('tr.member-row')` filtered
 by `style.display !== 'none'`, finds the index whose `dataset.name`
 matches `currentMemberName`, and calls `showMember` on the next/previous
 visible row. Identical to Python lines 944-962 but uses `dataset.name`
 instead of parsing `childNodes[0].textContent`.
 ### 3. Wire `data-page` attribute
 Append `data-page="adults"` to the `filterContainer` div in `adults.tmpl`,
 `data-page="juniors"` in `juniors.tmpl`. One-line edit per template.
 ### 4. Unit test
 Extend [go/internal/web/html_handler_test.go](go/internal/web/html_handler_test.go)
 with assertions that the rendered HTML for `/adults` and `/juniors` contains:
 - `class="info-icon"` with the expected `data-name` per fixture row,
 - `id="memberModal"`,
 - `<script src="/static/js/member-detail.js"`,
 - `data-page="adults"` / `data-page="juniors"` on the filter container.
 These are markup-level checks only — the JS module behaviour is not unit
 tested in Go (would require headless-browser tooling that is out of scope
 for this milestone). Manual browser verification covers it.
 ## Critical files
 | Action | Path |
 |--------|------|
 | edit   | [go/internal/web/templates/adults.tmpl](go/internal/web/templates/adults.tmpl) — add `[i]` icon, modal markup, `data-page`, script tag |
 | edit   | [go/internal/web/templates/juniors.tmpl](go/internal/web/templates/juniors.tmpl) — same |
 | new    | `go/internal/web/static/js/member-detail.js` — modal module |
 | edit   | `go/internal/web/html_handler_test.go` — markup assertions |
 No changes to: `app.css` (already complete), `assets.go` (the `embed.FS`
 glob `static/js/*` already picks up new files), `server.go`, `render.go`,
 the API handlers, or any domain code.
 ## Reused existing infrastructure
 - [go/internal/web/api/handler.go](go/internal/web/api/handler.go) — `/api/adults`, `/api/juniors` already serve the modal's data
 - [go/internal/web/api/adults.go:27-42](go/internal/web/api/adults.go#L27-L42), [go/internal/web/api/juniors.go](go/internal/web/api/juniors.go) — typed responses
 - [go/internal/web/api/types.go:24-29](go/internal/web/api/types.go#L24-L29) — `Expected` "?" sentinel marshalling
 - [go/internal/web/static/css/app.css](go/internal/web/static/css/app.css) — modal CSS already lifted
 - [go/internal/web/static/js/filters.js](go/internal/web/static/js/filters.js) — IIFE / `'use strict'` / `data-*` attribute style to match
 - [templates/adults.html:725-962](templates/adults.html#L725-L962) — Python reference implementation to port (logic, not literal copy)
 ## Verification
 End-to-end:
 1. `cd go && make go-build go-test go-lint` — all green.
 2. `make web-go &` — boot Go on `:8080`.
 3. Browser: `http://localhost:8080/adults`
   - Click `[i]` next to a member name → modal opens with that member's data.
   - Status table populated; cells colour-coded (cell-ok / cell-unpaid).
   - Exception section visible only if member has exceptions; exception
     amount shown with "*" override style.
   - "Other Payments" section visible only if member has other-purpose
     transactions.
   - Matched transactions list newest-first; raw-payments section starts
     hidden, `[show]` toggles to `[hide]`.
   - `Esc` closes the modal; `ArrowDown` / `ArrowUp` walk visible rows
     (after applying name filter).
   - Click outside the `.modal-content` closes the modal.
   - Open DevTools Network tab → reload; confirm one request to `/api/adults`
     fires on page load (data is pre-warmed), no further requests on row
     click.
 4. Browser: `http://localhost:8080/juniors`
   - Same checks; verify `expected = "?"` rows render the question-mark
     status without throwing JS errors.
 5. Cross-check against Python: `make web-py &` → `http://localhost:5001/adults`
   should look visually equivalent (modulo nav styling) for the same fixture.
 6. After commit: `tea pr create --base main --head feat/go-m6-5-modal-js`.
 ## Branching
 Per [CLAUDE.md](CLAUDE.md): create `feat/go-m6-5-modal-js` off `main`,
 commit with `Co-Authored-By` trailer, push with `-u`, open MR via
 `tea pr create`. Do not merge from CLI. After the user merges in Gitea:
 - Add CHANGELOG entry (timestamp via `date "+%Y-%m-%d %H:%M %Z"`).
 - Tick **M6.5** in
  [docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md:117](docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md#L117)
  with the merge SHA.
 ## Out of scope (deferred)
 - **`/qr` modal** — separate `#qrModal` element, lives in M6.6 alongside
  `/sync-bank`, `/flush-cache`, `/version`.
 - **Pay buttons inside the modal** — Python's modal does not include
  Pay-from-modal; current Go pages already render row-level Pay buttons
  in M6.2/M6.3.
 - **Modal on `/payments`** — Python `/payments` has no modal, neither does
  Go (confirmed in M6.4 plan).
 - **Deep-linking (`/adults#name=Foo`)** — not in Python, not adding.
 - **Headless-browser JS tests** — out of scope for this milestone; manual
  browser verification per §Verification.
--- a/docs/plans/2026-05-08-1334-go-m6-6-action-pages.md
+++ b/docs/plans/2026-05-08-1334-go-m6-6-action-pages.md
@@ -0,0 +1,124 @@
 # M6.6 — `/qr`, `/sync-bank`, `/flush-cache`, `/version` (Go parity)
 > On approval, relocate this file to `docs/plans/YYYY-MM-DD-HHMM-go-m6-6-action-pages.md` per the repo's `CLAUDE.md` "Plans" convention before starting work.
 ## Context
 The Go-rewrite progress tracker ([2026-05-03-2349-go-backend-rewrite-progress.md:118](docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md#L118)) lists M6.6 as:
 > `/qr, /sync-bank, /flush-cache, /version pages`
 After M6.4 (payments page) and M6.5 (member-detail modal JS), the only remaining pre-deployment HTML/action endpoints in Python that the Go binary doesn't yet implement are these four. The adults/juniors templates already produce `/qr?...` URLs via the `qrHref` / `qrHrefAll` helpers ([render.go:47-71](go/internal/web/render.go#L47-L71)) — the matching handler is the missing piece. `sync` and `flush_cache` templates exist as "Coming in M6.6" stubs and need real markup + working handlers. `/api/version` already serves build metadata; `/version` just needs to alias it (Python parity).
 After M6.6 the M6 gate ("Browser smoke on :8080: all pages render … QR loads, sync/flush work end-to-end") is reachable.
 ## Confirmed design choices
 - **`/sync-bank`**: Python-faithful — GET both renders and triggers the sync, captures stdout/stderr into a log buffer, surfaces success/failure via a flag. Matches existing nav `[Sync Bank Data]` link.
 - **`/version`**: JSON alias of `/api/version`. No HTML page.
 - **QR library**: `github.com/skip2/go-qrcode`. Default level `qrcode.Medium`, size 256.
 ## Scope per endpoint
 ### 1. `GET /qr` — PNG only
 Match Python ([app.py:321-356](app.py#L321-L356)) verbatim semantics:
 1. Read `account` (default `cfg.BankAccount`), `amount` (default `"0"`), `message` (default `""`).
 2. Validate account against `^[A-Z]{2}\d{2,34}$|^\d{1,16}/\d{4}$`; on miss, silently fall back to `cfg.BankAccount`.
 3. Parse amount as float64; clamp to `[0, 10_000_000]`; format `%.2f`; on parse error → `"0.00"`.
 4. Truncate message to 60 runes; strip all `*`.
 5. If account contains `/`, split into `{number}*BC:{bankcode}`; else use raw.
 6. SPD payload: `SPD*1.0*ACC:{acc}*AM:{amount}*CC:CZK*MSG:{msg}` (no `BC:` key when IBAN — Python doesn't either).
 7. `qrcode.Encode(payload, qrcode.Medium, 256)` → write bytes with `Content-Type: image/png`.
 No template, no HTML.
 ### 2. `GET /sync-bank` — triggers + renders
 Match Python ([app.py:124-151](app.py#L124-L151)):
 1. Build a `*bytes.Buffer` to capture step output.
 2. For each step write a header line then call:
   - `banksync.SyncToSheets(ctx, cfg.PaymentsSheetID, fioClient, sheetsClient, banksync.SyncOpts{From: jan1ThisYear, To: dec31ThisYear, Sort: true})`
   - `banksync.InferPayments(ctx, cfg.PaymentsSheetID, sheetsClient, sources, banksync.InferOpts{})`
   - `cacheFlusher.Flush()` — append `"%d cache files deleted"`.
 3. On any error: append `err.Error()` + a stack trace via `runtime/debug.Stack()`, set `success=false`, continue rendering.
 4. Render `sync` template with `SyncPageData{ PageData; Output string; Success bool }`.
 The `banksync` package's stdout-printing functions can be redirected by passing an `io.Writer` — confirm during implementation; if they only print to `os.Stdout`, capture by tee'ing through a `slog` handler or briefly swapping `os.Stdout` (or extend the package with a `*Writer` option). **Preferred**: add a `Logger io.Writer` field to `banksync.SyncOpts` / `InferOpts`. This is a minor extension to existing services, not a rewrite.
 ### 3. `/flush-cache` — GET form, POST action
 Match Python ([app.py:117-122](app.py#L117-L122)):
 - `GET` → render `flush_cache` with `Flushed=false`.
 - `POST` → call `cacheFlusher.Flush()`, render with `Flushed=true, Deleted=n`.
 ### 4. `GET /version` — JSON
 One-liner: register the existing `api.VersionHandler` (or its inline equivalent in [api/version.go](go/internal/web/api/version.go)) on the `/version` path as well as `/api/version`. Output: `{"tag", "commit", "build_date"}`.
 ## Files to create / modify
 ### New files
 - **[go/internal/web/templates/qr.tmpl](go/internal/web/templates/qr.tmpl)** — *not actually needed*; remove from plan if `/qr` is PNG-only. (Decision: skip — no template.)
 - Replace stub **[go/internal/web/templates/sync.tmpl](go/internal/web/templates/sync.tmpl)** with full markup: title, status banner colored by `Success`, `<pre>` of `Output`, "Run again" link.
 - Replace stub **[go/internal/web/templates/flush_cache.tmpl](go/internal/web/templates/flush_cache.tmpl)** with: form (`POST /flush-cache` → `<button>[Flush Cache]</button>`), success banner when `Flushed`.
 ### Modified files
 - **[go/go.mod](go/go.mod)** / `go.sum` — add `github.com/skip2/go-qrcode`.
 - **[go/internal/web/server.go](go/internal/web/server.go)** — register `GET /qr`, `GET /sync-bank` (replace stub), `GET /flush-cache` (form), `POST /flush-cache` (action), `GET /version`. Widen `Run(...)` signature to accept `fio.Client`, `sheets.Client`, and a `cache.Flusher` — these flow into a new `Deps` struct on `HTMLHandler`.
 - **[go/internal/web/html_handler.go](go/internal/web/html_handler.go)** — add `ServeQR`, real `ServeSync`, split `ServeFlushCacheGET` / `ServeFlushCachePOST`, add `ServeVersion` (delegates to api package).
 - **[go/internal/web/render.go](go/internal/web/render.go)** — add `SyncPageData{ PageData; Output string; Success bool }` and `FlushPageData{ PageData; Flushed bool; Deleted int }` view-models. (`pageNames` already includes `"sync"` and `"flush_cache"`; no change.)
 - **[go/internal/web/qr.go](go/internal/web/qr.go)** *(new file)* — pure helper: `BuildSPD(account, amount, message string, defaultAccount string) (payload string)` + `RenderQRCode(payload string) ([]byte, error)`. Easier to unit-test than a method on the handler.
 - **[go/internal/services/membership/loader.go](go/internal/services/membership/loader.go)** — add a small `CacheFlusher` interface (`Flush() (int, error)`); have `Sources` aggregate include it. *Alternative considered*: pass `*cache.FileCache` straight into `web.Run`. Choose whichever needs fewer test-stub edits — likely the direct-pass approach, since stubs in tests don't need cache behavior. **Decision: pass `cache.Flusher` directly into `web.Run` as a separate dependency, not through `Sources`.** Simpler, fewer interface changes.
 - **[go/internal/services/banksync/sync.go](go/internal/services/banksync/sync.go)** + `infer.go` — accept an optional `io.Writer` (in `SyncOpts.Logger` / `InferOpts.Logger`) and route progress prints through it; default to `os.Stdout` when nil for CLI parity.
 - **[go/cmd/fuj/main.go](go/cmd/fuj/main.go)** — in the `server` subcommand, build `fio.Client`, `sheets.Client`, and `cache.Flusher` (already constructed inside `membership.NewSources` — expose it or construct a sibling) and pass them into `web.Run`.
 ## Reuse (already in the codebase)
 - **Bank sync**: `banksync.SyncToSheets` ([go/internal/services/banksync/sync.go](go/internal/services/banksync/sync.go)) and `banksync.InferPayments` ([go/internal/services/banksync/infer.go](go/internal/services/banksync/infer.go)) — same calls the CLI `sync` / `infer` subcommands use ([go/cmd/fuj/main.go:184](go/cmd/fuj/main.go#L184), [:222](go/cmd/fuj/main.go#L222)).
 - **Cache flush**: `(*cache.FileCache).Flush() (int, error)` ([go/internal/io/cache/filecache.go:92](go/internal/io/cache/filecache.go#L92)) — already returns the deleted count.
 - **Build metadata**: `BuildInfo{Version, Commit, BuildDate}` ([go/internal/web/server.go:28-35](go/internal/web/server.go#L28-L35)) is already plumbed everywhere; `/api/version` JSON shape is already correct ([go/internal/web/api/version.go](go/internal/web/api/version.go)).
 - **Template render pattern**: `Renderer.Render(w, name, data)` ([go/internal/web/render.go:98-108](go/internal/web/render.go#L98-L108)).
 - **Test scaffolding**: `web.NewRenderer()` + `httptest.NewRequest/NewRecorder` ([go/internal/web/html_handler_test.go:52-94](go/internal/web/html_handler_test.go#L52-L94)).
 ## Tests
 Add to `go/internal/web/html_handler_test.go` (and one new `qr_test.go` for the SPD builder):
 - **`TestQRBuildSPD`** *(unit, in [go/internal/web/qr_test.go](go/internal/web/qr_test.go))* — table-driven: invalid account → fallback; `/`-account → `{num}*BC:{bc}`; IBAN → raw; amount `-1` → `0.00`; amount `99999999` → `9999999.00`; amount `"abc"` → `0.00`; message with `*` stripped; message length-clamped to 60.
 - **`TestServeQR`** — request `/qr?account=…&amount=10&message=Hi`; assert 200, `Content-Type: image/png`, body starts with PNG magic `\x89PNG\r\n\x1a\n`.
 - **`TestServeFlushCacheGet`** — assert form rendered, no banner.
 - **`TestServeFlushCachePost`** — fixture flusher returns 3; assert banner says "3" and `Flushed`.
 - **`TestServeSync`** — fixture banksync stubs return `(2, nil)` and `(1, nil)`, fixture flusher returns 4; assert page renders, status is success, output contains the section headers.
 - **`TestServeVersion`** — assert `application/json`, body `{"tag":"v0","commit":"abc1234","build_date":"2026-01-01"}`.
 - Extend the `TestHTMLHandlerSmoke` table to cover `/qr` and `/version`.
 ## Verification (end-to-end)
 1. `cd go && go build ./... && go test ./...`
 2. `cd go && go run ./cmd/fuj server` — open http://localhost:8080
 3. Smoke:
   - **/adults** → click `Pay` next to any unpaid month → modal shows QR image (this exercises `/qr`). Confirm a Czech banking app can scan it (visual check).
   - Direct `/qr?account=2702008874/2010&amount=700&message=Test` → PNG renders.
   - **/sync-bank** → click `[Sync Bank Data]` in nav → page shows "Syncing…", then sections + "Inferred Payments", "Cache Flushed", green status banner.
   - **/flush-cache** → click `[Flush Cache]` → success banner with file count.
   - **/version** in browser → JSON visible.
   - Adults / juniors / payments still render (no regressions from `Run` signature change).
 4. Run the parity diff: `go run ./cmd/parity` — `/api/version` must still match Python.
 5. Append a CHANGELOG entry per `CLAUDE.md`; tick `M6.6` in [docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md:118](docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md#L118).
 ## Branch / MR
 Per `CLAUDE.md` workflow: `feat/go-m6-6-action-pages` off `main`, push with `-u`, open with `tea pr create --base main --head feat/go-m6-6-action-pages`.
 ## Out of scope (deferred)
 - Auth / CSRF protection on `/sync-bank` and `/flush-cache` — Python has none either; deferred to M8 hardening.
 - M6.7 (single-binary embed verification) — separate ticket.
 - Streaming progress for `/sync-bank` (currently buffered until completion, like Python).
 - Configurable QR error-correction level / size.
--- a/docs/plans/2026-05-08-1439-go-m6-6-1-payment-qr-modal.md
+++ b/docs/plans/2026-05-08-1439-go-m6-6-1-payment-qr-modal.md
@@ -0,0 +1,335 @@
 # M6.6.1 — Pay-button QR popup modal (`/adults`, `/juniors`)
 > Plan-mode note: per project convention this plan should live at
 > `docs/plans/2026-05-08-1439-go-m6-6-1-payment-qr-modal.md`. The first
 > execution step after approval is to copy this file there.
 > Branch: `feat/go-m6-6-1-payment-qr-modal` off `main`.
 ## Context
 M6.6 ([docs/plans/2026-05-08-1334-go-m6-6-action-pages.md](docs/plans/2026-05-08-1334-go-m6-6-action-pages.md))
 landed the backend `/qr` PNG endpoint plus `/sync-bank`, `/flush-cache`,
 `/version`. While doing it, the **client-side** half of the Pay flow was
 collapsed from a modal-with-details into a plain `<a href="/qr?...">` —
 clicking Pay now navigates the whole tab to the raw PNG.
 The Python app instead opens an in-page `#qrModal` showing the QR image
 *plus* labelled details (account, amount, message, title), then closes
 the modal on outside-click or `[close]`
 ([templates/adults.html:631-648](templates/adults.html#L631-L648),
 JS at [templates/adults.html:963-993](templates/adults.html#L963-L993)).
 This is the UX the user expects from the dashboard — staying on the
 table while displaying the QR is significantly more practical than
 losing context to a fullscreen image.
 M6.6.1 restores parity: the Pay/Pay-All buttons open an in-page
 `#qrModal`, identical in structure to the Python original, driven by a
 new vanilla-JS module `payment-qr.js` that mirrors the `member-detail.js`
 convention from M6.5.
 All the building blocks are already in place:
 - **`/qr` endpoint** ships PNGs ([go/internal/web/qr.go](go/internal/web/qr.go), tested by [TestServeQR](go/internal/web/html_handler_test.go#L207-L231)).
 - **CSS** for `#qrModal .modal-content`, `.qr-image`, `.qr-details` is
  already in [go/internal/web/static/css/app.css:445-478](go/internal/web/static/css/app.css#L445-L478) — lifted during M6.1.
 - **Template helpers** `qrHref` / `qrHrefAll` ([go/internal/web/render.go:63-85](go/internal/web/render.go#L63-L85))
  already produce the correct query string + Czech `MM/YYYY` format
  for the `message=` param. They're useful for sanity (and for any
  no-JS fallback) but become dead code post-M6.6.1 — see §Out of scope.
 - **Bank account** is already exposed as `$.Data.BankAccount` to every
  template that has a Pay button.
 - **JS module convention**: `member-detail.js` is the M6.5 baseline —
  IIFE, `'use strict'`, event delegation off `data-*` attributes, no
  inline `onclick`, no globals leaked.
 ## Approach
 ### 1. Replace `<a href="{{qrHref ...}}">` with `<button data-...>`
 In [go/internal/web/templates/adults.tmpl](go/internal/web/templates/adults.tmpl)
 and [go/internal/web/templates/juniors.tmpl](go/internal/web/templates/juniors.tmpl)
 (both have identical Pay markup at lines 65 and 72):
 ```gotmpl
 <button type="button" class="pay-btn"
        data-name="{{$row.Name}}"
        data-amount="{{$cell.Amount}}"
        data-month="{{$cell.Month}}"
        data-raw-month="{{$cell.RawMonth}}">Pay</button>
 ```
 ```gotmpl
 <button type="button" class="pay-btn"
        data-name="{{$row.Name}}"
        data-amount="{{$row.PayableAmount}}"
        data-month="{{$row.UnpaidPeriods}}"
        data-raw-month="{{$row.RawUnpaidPeriods}}"
        data-pay-all="1">Pay All</button>
 ```
 Why `<button type="button">` and not `<a>`: the click no longer
 navigates — the JS handles it. `type="button"` prevents accidental form
 submission. A no-JS fallback could be added later by re-introducing
 `href="{{qrHref ...}}"` and letting the JS call `e.preventDefault()` —
 deferred until anyone actually asks (see §Out of scope).
 `data-month` carries the human-readable period (e.g. `January 2026`,
 or `January 2026 + February 2026` for Pay-All) which the modal title
 displays. `data-raw-month` carries the machine format (`2026-01`,
 `2026-01+2026-02`) which the JS converts to `MM/YYYY` for the QR
 message — same conversion Python's `showPayQR` does at
 [templates/adults.html:966-968](templates/adults.html#L966-L968).
 `data-pay-all` is purely informational; the JS doesn't actually need
 it (the same code path handles single + multi-period), but keeping it
 helps debugging and any future analytics.
 ### 2. Add `#qrModal` markup
 Append after the `#memberModal` block in both `adults.tmpl` and
 `juniors.tmpl` (around line 185 of adults, line 165 of juniors), mirroring
 [templates/adults.html:631-648](templates/adults.html#L631-L648) but
 using `class="active"` toggling (the convention M6.5 picked) instead of
 `style.display = 'block'`:
 ```gotmpl
 <div id="qrModal" onclick="if(event.target===this)this.classList.remove('active')">
  <div class="modal-content">
    <div class="modal-header">
      <div class="modal-title" id="qrTitle">Payment for —</div>
      <div class="close-btn" onclick="document.getElementById('qrModal').classList.remove('active')">[close]</div>
    </div>
    <div class="qr-image">
      <img id="qrImg" src="" alt="Payment QR Code">
    </div>
    <div class="qr-details">
      <div>Account: <span id="qrAccount"></span></div>
      <div>Amount: <span id="qrAmount"></span> CZK</div>
      <div>Message: <span id="qrMessage"></span></div>
    </div>
  </div>
 </div>
 ```
 The CSS already targets `#qrModal .modal-content` directly. To make the
 "hidden by default / visible when `.active`" toggle behave the same
 way `#memberModal` does, the existing CSS rules for `#memberModal`
 (`display:none`, `#memberModal.active { display: flex; }`) need a
 sibling pair for `#qrModal`. Audit `app.css` during implementation:
 - if `#qrModal` already has both rules, no change.
 - if it has only `display:none`, add `#qrModal.active { display: flex; }`.
 - if it has neither, add both.
 This is a 2-line CSS adjustment at most; tracked under §Critical files.
 ### 3. Bank account on the page
 The modal needs the bank account string for the `qrAccount` label and
 for building the `/qr?account=…` URL. Two clean options:
 **(a)** Read it from the `<button>`'s `data-bank-account` attribute.
 Per-button duplication, but trivially done in templates and keeps the JS
 module's surface tiny.
 **(b)** Stamp it once on the page as `<body data-bank-account="…">`
 (or on the existing `#filterContainer`).
 **Decision: (b)** — single stamping site, follows the same pattern
 M6.5 used for `data-page` on `#filterContainer`. Add
 `data-bank-account="{{.Data.BankAccount}}"` to `#filterContainer` in
 both templates (one-line edit each).
 ### 4. Create [go/internal/web/static/js/payment-qr.js](go/internal/web/static/js/payment-qr.js)
 A new module loaded with `<script src="/static/js/payment-qr.js" defer></script>`
 right after `member-detail.js` in both templates. Pure ES, no build
 step, IIFE, `'use strict'`. Skeleton — port of Python's `showPayQR`
 ([templates/adults.html:963-986](templates/adults.html#L963-L986))
 plus event wiring:
 ```js
 (function () {
  'use strict';
  const container = document.getElementById('filterContainer');
  if (!container) return;
  const bankAccount = container.dataset.bankAccount || '';
  const modal      = document.getElementById('qrModal');
  const titleEl    = document.getElementById('qrTitle');
  const imgEl      = document.getElementById('qrImg');
  const accountEl  = document.getElementById('qrAccount');
  const amountEl   = document.getElementById('qrAmount');
  const messageEl  = document.getElementById('qrMessage');
  if (!modal || !titleEl || !imgEl || !accountEl || !amountEl || !messageEl) return;
  // Convert "YYYY-MM" → "MM/YYYY"; "+"-joined ranges are converted piece-wise.
  // Mirrors templates/adults.html:966-968.
  function toCzechMonth(rawMonth) {
    return rawMonth.split('+')
      .map(p => p.replace(/^(\d{4})-(\d{2})$/, '$2/$1'))
      .join('+');
  }
  function showQR(name, amount, month, rawMonth) {
    const numericMonth = toCzechMonth(rawMonth);
    const message = `${name}: ${numericMonth}`;
    titleEl.innerText   = `Payment for ${month}`;
    accountEl.innerText = bankAccount;
    amountEl.innerText  = amount;
    messageEl.innerText = message;
    const url = '/qr?'
      + 'account=' + encodeURIComponent(bankAccount)
      + '&amount=' + encodeURIComponent(amount)
      + '&message=' + encodeURIComponent(message);
    imgEl.src = url;
    modal.classList.add('active');
  }
  function closeQR() { modal.classList.remove('active'); }
  // Event delegation: any .pay-btn click anywhere in the page.
  document.addEventListener('click', ev => {
    const btn = ev.target.closest('.pay-btn');
    if (!btn) return;
    ev.preventDefault();
    showQR(
      btn.dataset.name,
      btn.dataset.amount,
      btn.dataset.month,
      btn.dataset.rawMonth,
    );
  });
  document.addEventListener('keydown', e => {
    if (e.key === 'Escape' && modal.classList.contains('active')) closeQR();
  });
 }());
 ```
 Notes:
 - **Event delegation** (single listener on `document`) handles both Pay
  and Pay-All without enumerating buttons. It also survives any future
  re-render of the table without needing rebinding.
 - **Coexistence with `member-detail.js`**: `member-detail.js` listens
  for `Escape` too, but only acts when `#memberModal` is active; the
  new module similarly only acts when `#qrModal` is active. No collision.
 - **Pre-warming**: nothing to pre-warm — `/qr` is a tiny on-demand PNG
  and only fires when the user clicks.
 - **Inline `onclick`** on `[close]` and outside-click in the markup are
  carried over from the M6.5 modal style; consistent with `#memberModal`.
  (Switching the project's modal close pattern to data attributes is a
  separate cleanup, out of scope here.)
 ### 5. Tests
 Extend [go/internal/web/html_handler_test.go](go/internal/web/html_handler_test.go)
 with markup-level checks. Headless-browser JS is out of scope (same
 rationale as M6.5).
 In `TestModalMarkup` (or a sibling test, e.g. `TestPaymentQRMarkup`):
 - Body for `/adults` and `/juniors` contains
  `<script src="/static/js/payment-qr.js"`.
 - Body contains `id="qrModal"`, `id="qrImg"`, `id="qrAccount"`,
  `id="qrAmount"`, `id="qrMessage"`, `id="qrTitle"`.
 - The fixture row's Pay button is rendered as
  `<button … class="pay-btn" … data-name="Test Member" data-amount="…" data-raw-month="2026-01"`.
 - The fixture row's `.pay-btn` does **not** include `href=`.
 - `#filterContainer` has `data-bank-account="CZ0000000000000000000000"`
  (matching the test's `fixtureHandler` config).
 ### 6. Decide fate of `qrHref` / `qrHrefAll` template helpers
 Once Pay/Pay-All buttons are JS-driven, the helpers in
 [render.go:63-85](go/internal/web/render.go#L63-L85) have no callers.
 **Decision: delete them**, plus their entries in `tmplFuncs`. A
 no-JS fallback is not on the roadmap; if it ever becomes one, the
 helpers are easy to resurrect from git.
 The unit-test file currently has no direct tests for these helpers —
 nothing to remove from tests.
 ## Critical files
 | Action | Path |
 |--------|------|
 | edit   | [go/internal/web/templates/adults.tmpl](go/internal/web/templates/adults.tmpl) — Pay/Pay-All → `<button data-…>`; add `#qrModal`; add `data-bank-account` on filter container; add `<script src="/static/js/payment-qr.js" defer>` |
 | edit   | [go/internal/web/templates/juniors.tmpl](go/internal/web/templates/juniors.tmpl) — same |
 | new    | `go/internal/web/static/js/payment-qr.js` — modal module |
 | edit   | [go/internal/web/render.go](go/internal/web/render.go) — drop `qrHref`, `qrHrefAll`, and their `tmplFuncs` entries (and the `net/url`, `strconv` imports if no longer needed) |
 | edit   | [go/internal/web/static/css/app.css](go/internal/web/static/css/app.css) — verify / add `#qrModal { display:none; }` + `#qrModal.active { display:flex; }` rules |
 | edit   | [go/internal/web/html_handler_test.go](go/internal/web/html_handler_test.go) — markup assertions |
 No changes to: `assets.go` (`embed.FS` glob picks up new JS automatically),
 `server.go`, `html_handler.go`, the `/qr` handler, `cmd/fuj/main.go`, the
 API handlers, or any domain code.
 ## Reused existing infrastructure
 - [go/internal/web/qr.go](go/internal/web/qr.go) — `/qr?account=…&amount=…&message=…` endpoint serves the PNG already
 - [go/internal/web/static/css/app.css:445-478](go/internal/web/static/css/app.css#L445-L478) — modal CSS already lifted whole
 - [go/internal/web/static/js/member-detail.js](go/internal/web/static/js/member-detail.js) — IIFE / `'use strict'` / `data-*` style to mirror
 - [go/internal/web/api/types.go](go/internal/web/api/types.go) — `MemberRow.UnpaidPeriods` and `RawUnpaidPeriods` already populated for Pay-All
 - [templates/adults.html:631-648,963-986](templates/adults.html#L631-L648) — Python reference for both modal markup and `showPayQR` JS (logic to port, not literal copy)
 ## Verification
 End-to-end, after copying the plan into `docs/plans/`:
 1. `cd go && make go-build go-test go-lint` — all green.
 2. `make web-go &` — boot Go on `:8080`.
 3. Browser: `http://localhost:8080/adults`
   - Click `Pay` on any unpaid month → `#qrModal` opens with
     - title `Payment for <Month YYYY>`,
     - `qrAccount` matching `BANK_ACCOUNT`,
     - `qrAmount` matching the cell amount,
     - `qrMessage` formatted as `<Name>: MM/YYYY`,
     - QR image rendered from `/qr?…` (Network tab shows PNG response).
   - Tab does **not** navigate; URL stays `/adults`.
   - Click `Pay All` → modal opens with `+`-joined `MM/YYYY+MM/YYYY` message.
   - Click outside the modal-content → modal closes.
   - Click `[close]` → modal closes.
   - Press `Esc` → modal closes.
   - Open `[i]` member-detail modal first, then `Esc` → only that closes
     (verify both modals don't fight each other).
 4. Browser: `http://localhost:8080/juniors` — same checks. Verify Pay
   on a `"?"`-expected row doesn't appear (Pay button is conditional on
   `unpaid`/`partial` cells).
 5. Cross-check against Python: `make web-py &` →
   `http://localhost:5001/adults` modal looks visually equivalent for
   the same fixture (modulo any nav / theme differences already accepted
   in M6).
 6. Scan a QR with a Czech banking app (or `zbarimg` on the saved PNG) —
   payload starts with `SPD*1.0*ACC:` and the message decodes to
   `<Name>: MM/YYYY`.
 7. After the user merges in Gitea: append CHANGELOG entry (timestamp via
   `date "+%Y-%m-%d %H:%M %Z"`); add a new tick line for **M6.6.1** in
   [docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md](docs/plans/2026-05-03-2349-go-backend-rewrite-progress.md)
   immediately under the M6.6 line, in the same format as the other
   sub-bullets.
 ## Branching
 Per [CLAUDE.md](CLAUDE.md): create `feat/go-m6-6-1-payment-qr-modal` off
 `main`, commit with `Co-Authored-By` trailer, push with `-u`, open MR via
 `tea pr create`. Do not merge or delete from CLI.
 ## Out of scope (deferred)
 - **Pay button no-JS fallback** — feasible to keep `qrHref` and have
  the JS `preventDefault` an `<a>`, but no current need. Resurrect the
  helpers if asked.
 - **Modal pattern unification** — `#memberModal` and `#qrModal` use
  inline `onclick` for `[close]` and outside-click. Consistent with
  M6.5 but worth a follow-up to delegate-event everything.
 - **Pay-from-modal inside `#memberModal`** — Python doesn't have it, and
  no one's asked for it on the Go side.
 - **Per-button QR error-correction / size** — `/qr` is fixed at
  Medium/256, same as M6.6. Configurable via query param can be added if
  printing larger physical posters becomes a use case.
 - **`/payments` Pay buttons** — the payments page is a ledger view; it
  doesn't render Pay buttons in either backend.
--- a/docs/plans/2026-05-11-2353-fill-first-multi-month-allocation.md
+++ b/docs/plans/2026-05-11-2353-fill-first-multi-month-allocation.md
@@ -0,0 +1,184 @@
 # Fill-first multi-month payment allocation
 ## Context
 Matyáš Thér paid in two transactions:
 | # | Amount | Purpose             |
 |---|--------|---------------------|
 | 1 | 200    | `2026-02`           |
 | 2 | 550    | `2026-02, 2026-03`  |
 Total 750 = his expected fee for the two months (likely 2026-02 = 500, 2026-03 = 250 — junior tier or exception-adjusted). The app currently shows 2026-02 = **566** paid, 2026-03 = **183** paid. The user wants:
 > First use the second payment for the rest of 2026-02 (no more, no less), then put the remainder toward 2026-03.
 Both Python ([scripts/match_payments.py](scripts/match_payments.py)) and Go ([go/internal/domain/reconcile/reconcile.go](go/internal/domain/reconcile/reconcile.go)) have the same bug: when a single transaction's `in_window_share` is less than the sum of in-window expected fees, both fall into a **proportional** branch that splits the new transaction across months in proportion to each month's *total* expected fee — never consulting what prior transactions already paid into earlier months.
 Trace for txn 2:
 - `in_window = [(2026-02, 500), (2026-03, 250)]`, `total_expected = 750`, `in_window_share = 550`.
 - `550 < 750` → proportional:
  - 02 alloc = `550 × 500 / 750 = 366.67`
  - 03 alloc = `550 − 366.67 = 183.33`
 - Combined with txn 1's 200 → 02 = 566.67, 03 = 183.33 → display `566 / 183`. ✓ matches reported numbers.
 The fix: replace the greedy + proportional branches with a single **fill-first** loop that iterates `in_window` in user-supplied order (already chronological by convention from [scripts/infer_payments.py:151](scripts/infer_payments.py#L151)) and allocates `min(remaining, max(0, expected − paid_so_far))` to each month, with any final surplus going to the credit bucket. This collapses three cases (greedy / proportional / pure overflow) into one and naturally consults the ledger's `paid` field which is already updated by prior transactions in the same reconcile pass.
 The even-split branch (`total_expected == 0`, prepayment before fees known) stays untouched — different semantic, folding it in would silently change behavior.
 ## Changes
 ### Python — [scripts/match_payments.py:471-498](scripts/match_payments.py#L471-L498)
 Replace both `total_expected > 0` branches (current lines 471–498) with a single unified loop. Keep lines 466–469 above and the even-split fallback below (lines 499–510) as-is.
 ```python
            if total_expected > 0:
                # Fill-first: iterate in_window in matched_months order (chronological by
                # convention), allocate min(remaining, deficit) to each month, where
                # deficit accounts for prior transactions already credited to that month.
                # Any surplus after all in-window deficits are covered → credit bucket.
                remaining = in_window_share
                for m, exp in in_window:
                    paid_so_far = ledger[member_name][m]["paid"]
                    deficit = max(0.0, float(exp) - paid_so_far)
                    alloc = min(remaining, deficit)
                    if alloc <= 0:
                        continue
                    ledger[member_name][m]["paid"] += alloc
                    ledger[member_name][m]["transactions"].append({
                        "amount": alloc,
                        "date": tx["date"],
                        "sender": tx["sender"],
                        "message": tx["message"],
                        "confidence": confidence,
                    })
                    remaining -= alloc
                if remaining > 0:
                    credits[member_name] = credits.get(member_name, 0) + int(remaining)
            else:
                # … existing even-split branch (lines 499–510) unchanged …
 ```
 Note: skipping the `transactions.append` when `alloc <= 0` (e.g. month already fully paid by a prior txn) avoids zero-amount ghost rows in the per-month transaction list. This is a small UI-visible side effect; before committing, grep tests for assertions on `len(transactions)` per month to confirm nothing relies on the current "one row per (txn, month) regardless of alloc" behavior.
 ### Go — [go/internal/domain/reconcile/reconcile.go:320-357](go/internal/domain/reconcile/reconcile.go#L320-L357)
 Same shape — replace both `totalExpected > 0` branches. Even-split branch (lines 358–372) stays.
 ```go
            if totalExpected > 0 {
                // Fill-first; see Python reconcile() for rationale.
                remaining := inWindowShare
                for _, mw := range inWindow {
                    md := ledger[memberName][mw.month]
                    deficit := float64(mw.expected) - md.Paid
                    if deficit < 0 {
                        deficit = 0
                    }
                    alloc := remaining
                    if deficit < alloc {
                        alloc = deficit
                    }
                    if alloc <= 0 {
                        continue
                    }
                    md.Paid += alloc
                    md.Transactions = append(md.Transactions, TxEntry{
                        Amount:     alloc,
                        Date:       tx.Date,
                        Sender:     tx.Sender,
                        Message:    tx.Message,
                        Confidence: string(m.Confidence),
                    })
                    ledger[memberName][mw.month] = md
                    remaining -= alloc
                }
                if remaining > 0 {
                    credits[memberName] += int(remaining)
                }
            } else {
                // … existing even-split branch (lines 358–372) unchanged …
            }
 ```
 ### Tests
 #### Python — [tests/test_reconcile_exceptions.py](tests/test_reconcile_exceptions.py)
 1. **Rewrite `test_proportional_underpayment`** ([line 96](tests/test_reconcile_exceptions.py#L96)) — its current assertions (`paid_02 < 750`, `paid_03 < 350`, `paid_04 < 750`, and 02/04 equal allocation) are incompatible with fill-first. Under fill-first with the same fixture (1250 across `02:750, 03:350, 04:750`):
   - 02: `min(1250, 750) = 750` (full) → remaining 500
   - 03: `min(500, 350) = 350` (full) → remaining 150
   - 04: `min(150, 750) = 150` (partial) → remaining 0
   Replace assertions with these exact expected values, rename to `test_underpayment_fills_earliest_first`.
 2. **Add `test_fill_first_across_two_transactions`** — the Matyáš regression:
   ```python
   def test_fill_first_across_two_transactions(self):
       """Prior txn fills 02 partially; later txn finishes 02 then spills to 03."""
       members = [('Matyáš', 'A', {'2026-02': (500, 2), '2026-03': (250, 1)})]
       sorted_months = ['2026-02', '2026-03']
       tx1 = _tx('Matyáš', '2026-02', 200)
       tx2 = _tx('Matyáš', '2026-02, 2026-03', 550)
       result = reconcile(members, sorted_months, [tx1, tx2])
       months = result['members']['Matyáš']['months']
       self.assertAlmostEqual(months['2026-02']['paid'], 500, places=2)
       self.assertAlmostEqual(months['2026-03']['paid'], 250, places=2)
   ```
 3. `test_greedy_exact_match`, `test_greedy_overpayment_goes_to_credit`, `test_single_month_unchanged`, `test_two_members_multi_month` should pass unchanged — fill-first agrees with greedy when payment ≥ total expected.
 #### Go — [go/internal/domain/reconcile/reconcile_test.go](go/internal/domain/reconcile/reconcile_test.go)
 - Add `TestUnderpaymentFillsEarliestFirst` mirroring the rewritten Python test.
 - Add `TestFillFirstAcrossTwoTransactions` mirroring the Matyáš scenario.
 #### Parity — [go/tests/parity/reconcile/reconcile_parity_test.go](go/tests/parity/reconcile/reconcile_parity_test.go)
 Add a fixture for the Matyáš two-transaction case. Since both implementations change together and Python remains canonical, existing parity fixtures should continue to pass; verify after edits.
 ### Changelog — [CHANGELOG.md](CHANGELOG.md)
 Append top entry (use `date "+%Y-%m-%d %H:%M %Z"` at commit time):
 ```markdown
 ## 2026-05-11 23:55 CET — fill-first multi-month payment allocation
 - Multi-month payment allocation now fills the earliest in-window deficit first
  and spills the remainder to later months, accounting for prior transactions'
  contributions. Previously a single transaction was split proportionally to
  each month's total expected fee, ignoring earlier payments — surfaced by
  Matyáš Thér's two-payment 200+550 case showing 566/183 instead of 500/250.
 - scripts/match_payments.py, go/internal/domain/reconcile/reconcile.go, tests.
 ```
 ## Critical files
 - [scripts/match_payments.py](scripts/match_payments.py) — Python reconcile (canonical)
 - [go/internal/domain/reconcile/reconcile.go](go/internal/domain/reconcile/reconcile.go) — Go reconcile (mirrors Python)
 - [tests/test_reconcile_exceptions.py](tests/test_reconcile_exceptions.py) — rewrite `test_proportional_underpayment` + add Matyáš test
 - [go/internal/domain/reconcile/reconcile_test.go](go/internal/domain/reconcile/reconcile_test.go) — add Go tests
 - [go/tests/parity/reconcile/reconcile_parity_test.go](go/tests/parity/reconcile/reconcile_parity_test.go) — add parity fixture
 - [CHANGELOG.md](CHANGELOG.md) — top entry
 ## Verification
 1. `make test` — Python unit tests including the rewritten + new fill-first tests.
 2. `cd go && go test ./internal/domain/reconcile/... ./tests/parity/reconcile/...` — Go unit + parity tests.
 3. `make web` → load `/adults` or `/juniors` (whichever lists Matyáš Thér) → his 2026-02 row should be fully paid (no shortfall), 2026-03 fully paid, no leftover credit.
 4. Spot-check one other multi-month-purpose member to make sure fully-covered cases still look right.
 ## Branch & MR (per CLAUDE.md)
 1. `git checkout -b fix/fill-first-multi-month-allocation`
 2. Apply edits + tests + CHANGELOG entry.
 3. `make test && (cd go && go test ./...)` — both green.
 4. Commit: `fix(reconcile): fill earliest month deficit first in multi-month allocations` with `Co-Authored-By` trailer.
 5. `git push -u origin fix/fill-first-multi-month-allocation`
 6. `tea pr create --title "fix(reconcile): fill earliest month deficit first" --description "<body>" --base main --head fix/fill-first-multi-month-allocation`
 7. Print MR URL. Do not merge from CLI.
--- a/go/cmd/fuj/main.go
+++ b/go/cmd/fuj/main.go
@@ -11,6 +11,7 @@ import (
 	"fuj-management/go/internal/services/banksync"
 	"fuj-management/go/internal/services/membership"
 	"fuj-management/go/internal/web"
 	"io"
 	"log/slog"
 	"os"
 	"time"
@@ -82,9 +83,40 @@ func serverCmd(args []string) {
 		os.Exit(1)
 	}
 	sheetsCli, err := sheets.New(ctx, cfg.CredentialsPath, cfg.DriveTimeout)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "fuj server: sheets client for sync: %v\n", err)
 		os.Exit(1)
 	}
 	fioCli := fio.New(cfg.FioAPIToken, config.IBANAccountNum(cfg.BankAccount), nil)
 	actions := web.ActionHandlers{
 		BankSync: func(ctx context.Context, out io.Writer) error {
 			yr := time.Now().Year()
 			from := time.Date(yr, 1, 1, 0, 0, 0, 0, time.UTC)
 			to := time.Date(yr, 12, 31, 23, 59, 59, 0, time.UTC)
 			fmt.Fprintln(out, "=== Sync Fio Transactions ===")
 			n, err := banksync.SyncToSheets(ctx, config.PaymentsSheetID, fioCli, sheetsCli,
 				banksync.SyncOpts{From: from, To: to, Sort: true})
 			if err != nil {
 				return fmt.Errorf("sync: %w", err)
 			}
 			fmt.Fprintf(out, "Synced %d new transaction(s).\n\n", n)
 			fmt.Fprintln(out, "=== Infer Payments ===")
 			n, err = banksync.InferPayments(ctx, config.PaymentsSheetID, sheetsCli, sources, banksync.InferOpts{})
 			if err != nil {
 				return fmt.Errorf("infer: %w", err)
 			}
 			fmt.Fprintf(out, "Inferred %d row(s).\n", n)
 			return nil
 		},
 	}
 	build := web.BuildInfo{Version: version, Commit: commit, BuildDate: buildDate}
-	if err := web.Run(logger, cfg.ServerAddr, build, sources, cfg); err != nil {
+	if err := web.Run(logger, cfg.ServerAddr, build, sources, cfg, actions); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
--- a/go/go.mod
+++ b/go/go.mod
@@ -5,6 +5,7 @@ go 1.26.1
 require (
 	github.com/google/go-cmp v0.7.0
 	github.com/invopop/jsonschema v0.14.0
 	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e
 	golang.org/x/net v0.53.0
 	golang.org/x/text v0.36.0
 	google.golang.org/api v0.278.0
--- a/go/go.sum
+++ b/go/go.sum
@@ -37,6 +37,8 @@ github.com/pb33f/ordered-map/v2 v2.3.1 h1:5319HDO0aw4DA4gzi+zv4FXU9UlSs3xGZ40wcP
 github.com/pb33f/ordered-map/v2 v2.3.1/go.mod h1:qxFQgd0PkVUtOMCkTapqotNgzRhMPL7VvaHKbd1HnmQ=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e h1:MRM5ITcdelLK2j1vwZ3Je0FKVCfqOLp5zO6trqMLYs0=
 github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e/go.mod h1:XV66xRDqSt+GTGFMVlhk3ULuV0y9ZmzeVGR4mloJI3M=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
--- a/go/internal/domain/reconcile/reconcile.go
+++ b/go/internal/domain/reconcile/reconcile.go
@@ -115,10 +115,11 @@ type monthExpected struct {
 	expected int
 }
-// Reconcile matches transactions to members and months using three allocation phases:
+// Reconcile matches transactions to members and months using two allocation phases:
-//  1. Greedy: payment ≥ total expected → fill each month exactly; overflow → credit.
+//  1. Fill-first: iterate matched months in user-supplied order, allocating min(remaining,
-//  2. Proportional: payment < total → distribute by each month's share; last absorbs float remainder.
+//     deficit) to each month where deficit = expected − already-paid. Surplus → credit.
-//  3. Even-split fallback: all expected fees are 0 (prepayment) → divide equally.
+//     Handles both the "greedy" (payment covers all) and "partial" cases in one pass.
 //  2. Even-split fallback: all expected fees are 0 (prepayment) → divide equally.
 //
 // defaultYear seeds czech.ParseMonthReferences in the inference fallback.
 // Pass time.Now().Year() in production; pass a fixed year in tests.
@@ -317,34 +318,26 @@ func Reconcile(
 				totalExpected += mw.expected
 			}
-			if totalExpected > 0 && inWindowShare >= float64(totalExpected) {
+			if totalExpected > 0 {
-				// Greedy: payment covers all expected fees; overflow → credit
+				// Fill-first: iterate inWindow in matched-months order (chronological by
-				credits[memberName] += int(inWindowShare - float64(totalExpected))
+				// convention), allocating min(remaining, deficit) to each month. Deficit
-				for _, mw := range inWindow {
+				// is net of what prior transactions already paid, so a second payment on
-					alloc := float64(mw.expected)
+				// the same months correctly fills only what remains due. Any surplus after
-					md := ledger[memberName][mw.month]
+				// all deficits are covered goes to the credit bucket.
 					md.Paid += alloc
 					md.Transactions = append(md.Transactions, TxEntry{
 						Amount:     alloc,
 						Date:       tx.Date,
 						Sender:     tx.Sender,
 						Message:    tx.Message,
 						Confidence: string(m.Confidence),
 					})
 					ledger[memberName][mw.month] = md
 				}
 			} else if totalExpected > 0 {
 				// Proportional: distribute by each month's share; last month absorbs float remainder
 				remaining := inWindowShare
-				for i, mw := range inWindow {
+				for _, mw := range inWindow {
 					var alloc float64
 					if i == len(inWindow)-1 {
 						alloc = remaining
 					} else {
 						alloc = inWindowShare * float64(mw.expected) / float64(totalExpected)
 					}
 					remaining -= alloc
 					md := ledger[memberName][mw.month]
 					deficit := float64(mw.expected) - md.Paid
 					if deficit < 0 {
 						deficit = 0
 					}
 					alloc := remaining
 					if deficit < alloc {
 						alloc = deficit
 					}
 					if alloc <= 0 {
 						continue
 					}
 					md.Paid += alloc
 					md.Transactions = append(md.Transactions, TxEntry{
 						Amount:     alloc,
@@ -354,6 +347,10 @@ func Reconcile(
 						Confidence: string(m.Confidence),
 					})
 					ledger[memberName][mw.month] = md
 					remaining -= alloc
 				}
 				if remaining > 0 {
 					credits[memberName] += int(remaining)
 				}
 			} else {
 				// Even-split fallback: prepayment before attendance recorded
--- a/go/internal/domain/reconcile/reconcile_test.go
+++ b/go/internal/domain/reconcile/reconcile_test.go
@@ -111,36 +111,26 @@ func TestReconcileGreedyOverpaymentGoesToCredit(t *testing.T) {
 	}
 }
-func TestReconcileProportionalUnderpayment(t *testing.T) {
+func TestReconcileUnderpaymentFillsEarliestFirst(t *testing.T) {
 	t.Parallel()
 	members := []Member{{
 		Name: "Alice", Tier: "A",
 		Fees: map[string]FeeData{"2026-02": {Expected: 750, Attendance: 3}, "2026-03": {Expected: 350, Attendance: 3}, "2026-04": {Expected: 750, Attendance: 3}},
 	}}
 	sortedMonths := []string{"2026-02", "2026-03", "2026-04"}
 	amount := 1250.0
-	result := Reconcile(members, sortedMonths, []Transaction{tx("Alice", "2026-02, 2026-03, 2026-04", amount)}, nil, defaultYear)
+	result := Reconcile(members, sortedMonths, []Transaction{tx("Alice", "2026-02, 2026-03, 2026-04", 1250)}, nil, defaultYear)
 	months := result.Members["Alice"].Months
-	paid02 := months["2026-02"].Paid
+	// 02 filled first (750), then 03 (350), then remainder 150 to 04
-	paid03 := months["2026-03"].Paid
+	if math.Abs(months["2026-02"].Paid-750) > 0.01 {
-	paid04 := months["2026-04"].Paid
+		t.Errorf("02: want 750, got %f", months["2026-02"].Paid)
 	if paid02 >= 750 {
 		t.Errorf("2026-02 should be underpaid, got %f", paid02)
 	}
-	if paid03 >= 350 {
+	if math.Abs(months["2026-03"].Paid-350) > 0.01 {
-		t.Errorf("2026-03 should be underpaid, got %f", paid03)
+		t.Errorf("03: want 350, got %f", months["2026-03"].Paid)
 	}
-	if paid04 >= 750 {
+	if math.Abs(months["2026-04"].Paid-150) > 0.01 {
-		t.Errorf("2026-04 should be underpaid, got %f", paid04)
+		t.Errorf("04: want 150, got %f", months["2026-04"].Paid)
 	}
 	if math.Abs(paid02+paid03+paid04-amount) > 0.01 {
 		t.Errorf("sum of paid want %f, got %f", amount, paid02+paid03+paid04)
 	}
 	if math.Abs(paid02-paid04) > 0.01 {
 		t.Errorf("02 and 04 have equal expected, want equal paid: %f vs %f", paid02, paid04)
 	}
 }
@@ -374,3 +364,52 @@ func TestReconcileNoTransactionsAllUnpaid(t *testing.T) {
 		t.Errorf("no txs: want empty unmatched, got %v", result.Unmatched)
 	}
 }
 // Payment < total expected → fill earliest months first, spill remainder to later.
 func TestUnderpaymentFillsEarliestFirst(t *testing.T) {
 	t.Parallel()
 	members := []Member{{Name: "Alice", Tier: "A", Fees: map[string]FeeData{
 		"2026-02": {Expected: 750, Attendance: 3},
 		"2026-03": {Expected: 350, Attendance: 3},
 		"2026-04": {Expected: 750, Attendance: 3},
 	}}}
 	txs := []Transaction{tx("Alice", "2026-02, 2026-03, 2026-04", 1250)}
 	result := Reconcile(members, []string{"2026-02", "2026-03", "2026-04"}, txs, nil, defaultYear)
 	months := result.Members["Alice"].Months
 	// 02 filled first (750), then 03 (350), then remainder 150 to 04
 	if math.Abs(months["2026-02"].Paid-750) > 0.01 {
 		t.Errorf("02: want 750, got %f", months["2026-02"].Paid)
 	}
 	if math.Abs(months["2026-03"].Paid-350) > 0.01 {
 		t.Errorf("03: want 350, got %f", months["2026-03"].Paid)
 	}
 	if math.Abs(months["2026-04"].Paid-150) > 0.01 {
 		t.Errorf("04: want 150, got %f", months["2026-04"].Paid)
 	}
 }
 // Prior txn fills 02 partially; later txn finishes 02 then spills to 03.
 func TestFillFirstAcrossTwoTransactions(t *testing.T) {
 	t.Parallel()
 	members := []Member{{Name: "Matyáš", Tier: "A", Fees: map[string]FeeData{
 		"2026-02": {Expected: 500, Attendance: 2},
 		"2026-03": {Expected: 250, Attendance: 1},
 	}}}
 	sortedMonths := []string{"2026-02", "2026-03"}
 	txs := []Transaction{
 		tx("Matyáš", "2026-02", 200),
 		tx("Matyáš", "2026-02, 2026-03", 550),
 	}
 	result := Reconcile(members, sortedMonths, txs, nil, defaultYear)
 	months := result.Members["Matyáš"].Months
 	if math.Abs(months["2026-02"].Paid-500) > 0.01 {
 		t.Errorf("02: want 500, got %f", months["2026-02"].Paid)
 	}
 	if math.Abs(months["2026-03"].Paid-250) > 0.01 {
 		t.Errorf("03: want 250, got %f", months["2026-03"].Paid)
 	}
 }
--- a/go/internal/services/membership/loader.go
+++ b/go/internal/services/membership/loader.go
@@ -25,11 +25,17 @@ type ExceptionLoader interface {
 	LoadExceptions(ctx context.Context) (map[reconcile.ExceptionKey]reconcile.Exception, error)
 }
 // CacheFlusher can invalidate all cached data.
 type CacheFlusher interface {
 	FlushCache() (int, error)
 }
 // Sources is the aggregate interface required by ReconcileReport.
 type Sources interface {
 	AttendanceLoader
 	TransactionLoader
 	ExceptionLoader
 	CacheFlusher
 }
 // NewStubSources returns a Sources whose every method returns ErrIOPending.
@@ -52,3 +58,5 @@ func (stubSources) LoadTransactions(_ context.Context) ([]reconcile.Transaction,
 func (stubSources) LoadExceptions(_ context.Context) (map[reconcile.ExceptionKey]reconcile.Exception, error) {
 	return nil, ErrIOPending
 }
 func (stubSources) FlushCache() (int, error) { return 0, nil }
--- a/go/internal/services/membership/reconcile_test.go
+++ b/go/internal/services/membership/reconcile_test.go
@@ -31,6 +31,8 @@ func (f fakeSources) LoadExceptions(_ context.Context) (map[reconcile.ExceptionK
 	return f.exceptions, nil
 }
 func (fakeSources) FlushCache() (int, error) { return 0, nil }
 func TestReconcileReport(t *testing.T) {
 	t.Parallel()
 	s := fakeSources{
--- a/go/internal/services/membership/sources.go
+++ b/go/internal/services/membership/sources.go
@@ -111,6 +111,9 @@ func (s *realSources) LoadTransactions(ctx context.Context) ([]reconcile.Transac
 	return parseTransactionRows(rows)
 }
 // FlushCache deletes all cached data files and resets in-memory cache state.
 func (s *realSources) FlushCache() (int, error) { return s.cache.Flush() }
 // LoadExceptions fetches the exceptions tab (cached).
 func (s *realSources) LoadExceptions(ctx context.Context) (map[reconcile.ExceptionKey]reconcile.Exception, error) {
 	rows, err := cache.Get(ctx, s.cache, "exceptions_dict",
--- a/go/internal/web/api/handler.go
+++ b/go/internal/web/api/handler.go
@@ -23,6 +23,9 @@ type Handler struct {
 	Logger       *slog.Logger
 }
 // FlushCache invalidates all cached data via the underlying Sources.
 func (h *Handler) FlushCache() (int, error) { return h.Sources.FlushCache() }
 // ServeVersion handles GET /api/version.
 func (h *Handler) ServeVersion(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, VersionResponse{
@@ -55,25 +58,43 @@ func (h *Handler) AssembleAdults(ctx context.Context) (AdultsResponse, error) {
 // ServeJuniors handles GET /api/juniors.
 func (h *Handler) ServeJuniors(w http.ResponseWriter, r *http.Request) {
-	ctx := r.Context()
+	resp, err := h.AssembleJuniors(r.Context())
 	members, sortedMonths, txns, exceptions, err := h.loadAll(ctx, false)
 	if err != nil {
 		h.writeError(w, r, err)
 		return
 	}
 	writeJSON(w, resp)
 }
 // AssembleJuniors loads all data and builds the juniors view model.
 // Shared between the JSON API route and the HTML handler.
 func (h *Handler) AssembleJuniors(ctx context.Context) (JuniorsResponse, error) {
 	members, sortedMonths, txns, exceptions, err := h.loadAll(ctx, false)
 	if err != nil {
 		return JuniorsResponse{}, err
 	}
 	result := domreconcile.Reconcile(members, sortedMonths, txns, exceptions, time.Now().Year())
-	writeJSON(w, buildJuniorsResponse(members, sortedMonths, result, txns, h.Config, time.Now().Format("2006-01")))
+	return buildJuniorsResponse(members, sortedMonths, result, txns, h.Config, time.Now().Format("2006-01")), nil
 }
 // ServePayments handles GET /api/payments.
 func (h *Handler) ServePayments(w http.ResponseWriter, r *http.Request) {
-	ctx := r.Context()
+	resp, err := h.AssemblePayments(r.Context())
 	txns, err := h.Sources.LoadTransactions(ctx)
 	if err != nil {
-		h.writeError(w, r, fmt.Errorf("load transactions: %w", err))
+		h.writeError(w, r, err)
 		return
 	}
-	writeJSON(w, buildPaymentsResponse(txns, h.allMemberNames(ctx)))
+	writeJSON(w, resp)
 }
 // AssemblePayments loads transactions and builds the payments view model.
 // Shared between the JSON API route and the HTML handler.
 func (h *Handler) AssemblePayments(ctx context.Context) (PaymentsResponse, error) {
 	txns, err := h.Sources.LoadTransactions(ctx)
 	if err != nil {
 		return PaymentsResponse{}, fmt.Errorf("load transactions: %w", err)
 	}
 	return buildPaymentsResponse(txns, h.allMemberNames(ctx)), nil
 }
 func (h *Handler) loadAll(ctx context.Context, adults bool) (
--- a/go/internal/web/html_handler.go
+++ b/go/internal/web/html_handler.go
@@ -1,8 +1,11 @@
 package web
 import (
 	"bytes"
 	"fmt"
 	"fuj-management/go/internal/web/api"
 	"net/http"
 	"runtime/debug"
 )
 // HTMLHandler serves the Go-native HTML frontend.
@@ -10,11 +13,12 @@ type HTMLHandler struct {
 	renderer   *Renderer
 	build      BuildInfo
 	apiHandler *api.Handler
 	actions    ActionHandlers
 }
 // NewHTMLHandler constructs an HTMLHandler.
-func NewHTMLHandler(r *Renderer, b BuildInfo, ah *api.Handler) *HTMLHandler {
+func NewHTMLHandler(r *Renderer, b BuildInfo, ah *api.Handler, actions ActionHandlers) *HTMLHandler {
-	return &HTMLHandler{renderer: r, build: b, apiHandler: ah}
+	return &HTMLHandler{renderer: r, build: b, apiHandler: ah, actions: actions}
 }
 func (h *HTMLHandler) ServeAdults(w http.ResponseWriter, r *http.Request) {
@@ -33,17 +37,107 @@ func (h *HTMLHandler) ServeAdults(w http.ResponseWriter, r *http.Request) {
 }
 func (h *HTMLHandler) ServeJuniors(w http.ResponseWriter, r *http.Request) {
-	h.renderer.Render(w, "juniors", PageData{Active: "juniors", Build: h.build})
+	data, err := h.apiHandler.AssembleJuniors(r.Context())
 	if err != nil {
 		h.renderer.Render(w, "juniors", JuniorsPageData{
 			PageData: PageData{Active: "juniors", Build: h.build},
 			Error:    err.Error(),
 		})
 		return
 	}
 	h.renderer.Render(w, "juniors", JuniorsPageData{
 		PageData: PageData{Active: "juniors", Build: h.build},
 		Data:     data,
 	})
 }
 func (h *HTMLHandler) ServePayments(w http.ResponseWriter, r *http.Request) {
-	h.renderer.Render(w, "payments", PageData{Active: "payments", Build: h.build})
+	data, err := h.apiHandler.AssemblePayments(r.Context())
 	if err != nil {
 		h.renderer.Render(w, "payments", PaymentsPageData{
 			PageData: PageData{Active: "payments", Build: h.build},
 			Error:    err.Error(),
 		})
 		return
 	}
 	h.renderer.Render(w, "payments", PaymentsPageData{
 		PageData: PageData{Active: "payments", Build: h.build},
 		Data:     data,
 	})
 }
 // ServeSync handles GET /sync-bank: runs sync+infer+flush then renders the result.
 func (h *HTMLHandler) ServeSync(w http.ResponseWriter, r *http.Request) {
-	h.renderer.Render(w, "sync", PageData{Active: "sync", Build: h.build})
+	pd := PageData{Active: "sync", Build: h.build}
 	if h.actions.BankSync == nil {
 		h.renderer.Render(w, "sync", SyncPageData{
 			PageData: pd,
 			Output:   "Bank sync is not configured.",
 			Success:  false,
 		})
 		return
 	}
-func (h *HTMLHandler) ServeFlushCache(w http.ResponseWriter, r *http.Request) {
+	var buf bytes.Buffer
-	h.renderer.Render(w, "flush_cache", PageData{Active: "flush", Build: h.build})
+	success := true
 	if err := h.actions.BankSync(r.Context(), &buf); err != nil {
 		fmt.Fprintf(&buf, "\nError: %s\n\nStack trace:\n%s", err.Error(), debug.Stack())
 		success = false
 	}
 	fmt.Fprintln(&buf, "\n=== Flush Cache ===")
 	n, err := h.apiHandler.FlushCache()
 	if err != nil {
 		fmt.Fprintf(&buf, "flush error: %s\n", err.Error())
 		success = false
 	} else {
 		fmt.Fprintf(&buf, "%d cache file(s) deleted.\n", n)
 	}
 	h.renderer.Render(w, "sync", SyncPageData{
 		PageData: pd,
 		Output:   buf.String(),
 		Success:  success,
 	})
 }
 // ServeFlushCacheGET handles GET /flush-cache: renders the confirmation form.
 func (h *HTMLHandler) ServeFlushCacheGET(w http.ResponseWriter, r *http.Request) {
 	h.renderer.Render(w, "flush_cache", FlushPageData{
 		PageData: PageData{Active: "flush", Build: h.build},
 	})
 }
 // ServeFlushCachePOST handles POST /flush-cache: flushes and re-renders with count.
 func (h *HTMLHandler) ServeFlushCachePOST(w http.ResponseWriter, r *http.Request) {
 	n, _ := h.apiHandler.FlushCache()
 	h.renderer.Render(w, "flush_cache", FlushPageData{
 		PageData: PageData{Active: "flush", Build: h.build},
 		Flushed:  true,
 		Deleted:  n,
 	})
 }
 // ServeQR handles GET /qr: generates and returns a Czech QR Platba PNG.
 func (h *HTMLHandler) ServeQR(w http.ResponseWriter, r *http.Request) {
 	q := r.URL.Query()
 	account := q.Get("account")
 	amount := q.Get("amount")
 	message := q.Get("message")
 	if account == "" {
 		account = h.apiHandler.Config.BankAccount
 	}
 	if amount == "" {
 		amount = "0"
 	}
 	payload := BuildSPD(account, amount, message, h.apiHandler.Config.BankAccount)
 	png, err := RenderQRCode(payload)
 	if err != nil {
 		http.Error(w, "qr encode: "+err.Error(), http.StatusInternalServerError)
 		return
 	}
 	w.Header().Set("Content-Type", "image/png")
 	_, _ = w.Write(png)
 }
--- a/go/internal/web/html_handler_test.go
+++ b/go/internal/web/html_handler_test.go
@@ -1,12 +1,15 @@
 package web_test
 import (
 	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
 	"fuj-management/go/internal/config"
 	"fuj-management/go/internal/domain/reconcile"
 	"fuj-management/go/internal/web"
 	"fuj-management/go/internal/web/api"
 	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -41,6 +44,8 @@ func (fixtureSources) LoadExceptions(_ context.Context) (map[reconcile.Exception
 	return nil, nil
 }
 func (fixtureSources) FlushCache() (int, error) { return 0, nil }
 func fixtureHandler(t *testing.T) *api.Handler {
 	t.Helper()
 	return &api.Handler{
@@ -55,7 +60,7 @@ func TestHTMLHandlerSmoke(t *testing.T) {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
-	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t))
+	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	cases := []struct {
 		path    string
@@ -65,7 +70,7 @@ func TestHTMLHandlerSmoke(t *testing.T) {
 		{"/juniors", h.ServeJuniors},
 		{"/payments", h.ServePayments},
 		{"/sync-bank", h.ServeSync},
-		{"/flush-cache", h.ServeFlushCache},
+		{"/flush-cache", h.ServeFlushCacheGET},
 	}
 	for _, tc := range cases {
@@ -99,7 +104,7 @@ func TestAdultsPage(t *testing.T) {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
-	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t))
+	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	req := httptest.NewRequest(http.MethodGet, "/adults", nil)
 	w := httptest.NewRecorder()
@@ -126,3 +131,253 @@ func TestAdultsPage(t *testing.T) {
 		t.Error("body should not contain >OK<")
 	}
 }
 func TestModalMarkup(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	cases := []struct {
 		path    string
 		handler http.HandlerFunc
 		page    string
 		wantRow string // data-name present only when the page has rows
 	}{
 		{"/adults", h.ServeAdults, "adults", `data-name="Test Member"`},
 		{"/juniors", h.ServeJuniors, "juniors", ""},
 	}
 	for _, tc := range cases {
 		t.Run(tc.path, func(t *testing.T) {
 			req := httptest.NewRequest(http.MethodGet, tc.path, nil)
 			w := httptest.NewRecorder()
 			tc.handler(w, req)
 			body := w.Body.String()
 			for _, want := range []string{
 				`data-page="` + tc.page + `"`,
 				`id="memberModal"`,
 				`/static/js/member-detail.js`,
 			} {
 				if !strings.Contains(body, want) {
 					t.Errorf("body missing %q", want)
 				}
 			}
 			if tc.wantRow != "" && !strings.Contains(body, tc.wantRow) {
 				t.Errorf("body missing info-icon row %q", tc.wantRow)
 			}
 		})
 	}
 }
 func TestPaymentsPage(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	req := httptest.NewRequest(http.MethodGet, "/payments", nil)
 	w := httptest.NewRecorder()
 	h.ServePayments(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	body := w.Body.String()
 	for _, want := range []string{
 		"Payments Ledger",
 		"<h2>Test Member</h2>",
 		"750 CZK",
 		"2026-01-01",
 		"2026-01",
 	} {
 		if !strings.Contains(body, want) {
 			t.Errorf("body missing %q", want)
 		}
 	}
 }
 func TestServeQR(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	req := httptest.NewRequest(http.MethodGet, "/qr?account=2702008874%2F2010&amount=700&message=Test", nil)
 	w := httptest.NewRecorder()
 	h.ServeQR(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	if ct := w.Header().Get("Content-Type"); ct != "image/png" {
 		t.Errorf("Content-Type = %q, want image/png", ct)
 	}
 	// PNG magic bytes: \x89PNG\r\n\x1a\n
 	magic := []byte{0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a}
 	body := w.Body.Bytes()
 	if len(body) < len(magic) || !bytes.Equal(body[:len(magic)], magic) {
 		t.Error("response body does not start with PNG magic bytes")
 	}
 }
 func TestServeFlushCacheGET(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	req := httptest.NewRequest(http.MethodGet, "/flush-cache", nil)
 	w := httptest.NewRecorder()
 	h.ServeFlushCacheGET(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	body := w.Body.String()
 	if !strings.Contains(body, "Flush Cache") {
 		t.Error("body missing Flush Cache heading")
 	}
 	if strings.Contains(body, "file(s) deleted") {
 		t.Error("GET should not show deleted count")
 	}
 }
 func TestServeFlushCachePOST(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	req := httptest.NewRequest(http.MethodPost, "/flush-cache", nil)
 	w := httptest.NewRecorder()
 	h.ServeFlushCachePOST(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	body := w.Body.String()
 	// fixtureSources.FlushCache returns 0
 	if !strings.Contains(body, "file(s) deleted") {
 		t.Error("POST should show deleted count")
 	}
 }
 func TestServeSync(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	actions := web.ActionHandlers{
 		BankSync: func(_ context.Context, out io.Writer) error {
 			fmt.Fprintln(out, "=== Sync Fio Transactions ===")
 			fmt.Fprintln(out, "Synced 3 new transaction(s).")
 			fmt.Fprintln(out, "=== Infer Payments ===")
 			fmt.Fprintln(out, "Inferred 2 row(s).")
 			return nil
 		},
 	}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), actions)
 	req := httptest.NewRequest(http.MethodGet, "/sync-bank", nil)
 	w := httptest.NewRecorder()
 	h.ServeSync(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	body := w.Body.String()
 	for _, want := range []string{
 		"Sync Bank Data",
 		"Synced 3 new transaction(s).",
 		"Inferred 2 row(s).",
 		"Flush Cache",
 	} {
 		if !strings.Contains(body, want) {
 			t.Errorf("body missing %q", want)
 		}
 	}
 }
 func TestPaymentQRMarkup(t *testing.T) {
 	renderer, err := web.NewRenderer()
 	if err != nil {
 		t.Fatalf("NewRenderer: %v", err)
 	}
 	b := web.BuildInfo{Version: "v0", Commit: "abc1234", BuildDate: "2026-01-01"}
 	h := web.NewHTMLHandler(renderer, b, fixtureHandler(t), web.ActionHandlers{})
 	cases := []struct {
 		path    string
 		handler http.HandlerFunc
 	}{
 		{"/adults", h.ServeAdults},
 		{"/juniors", h.ServeJuniors},
 	}
 	for _, tc := range cases {
 		t.Run(tc.path, func(t *testing.T) {
 			req := httptest.NewRequest(http.MethodGet, tc.path, nil)
 			w := httptest.NewRecorder()
 			tc.handler(w, req)
 			body := w.Body.String()
 			for _, want := range []string{
 				`id="qrModal"`,
 				`id="qrImg"`,
 				`id="qrTitle"`,
 				`id="qrAccount"`,
 				`id="qrAmount"`,
 				`id="qrMessage"`,
 				`/static/js/payment-qr.js`,
 				`data-bank-account="CZ0000000000000000000000"`,
 			} {
 				if !strings.Contains(body, want) {
 					t.Errorf("body missing %q", want)
 				}
 			}
 			// Pay buttons must use <button>, never a bare href to /qr.
 			if strings.Contains(body, `href="/qr`) {
 				t.Error("body must not contain href=/qr (Pay buttons should be <button>, not <a>)")
 			}
 		})
 	}
 }
 func TestServeVersion(t *testing.T) {
 	req := httptest.NewRequest(http.MethodGet, "/api/version", nil)
 	w := httptest.NewRecorder()
 	fixtureHandler(t).ServeVersion(w, req)
 	if w.Code != http.StatusOK {
 		t.Fatalf("status = %d, want 200", w.Code)
 	}
 	if ct := w.Header().Get("Content-Type"); !strings.HasPrefix(ct, "application/json") {
 		t.Errorf("Content-Type = %q, want application/json", ct)
 	}
 	var raw map[string]json.RawMessage
 	if err := json.NewDecoder(w.Body).Decode(&raw); err != nil {
 		t.Fatalf("decode JSON: %v", err)
 	}
 	for _, key := range []string{"tag", "commit", "build_date"} {
 		if _, ok := raw[key]; !ok {
 			t.Errorf("JSON response missing key %q", key)
 		}
 	}
 }
--- a/go/internal/web/qr.go
+++ b/go/internal/web/qr.go
@@ -0,0 +1,50 @@
 package web
 import (
 	"fmt"
 	"regexp"
 	"strings"
 	"unicode/utf8"
 	qrcode "github.com/skip2/go-qrcode"
 )
 var validAccount = regexp.MustCompile(`^[A-Z]{2}\d{2,34}$|^\d{1,16}/\d{4}$`)
 // BuildSPD builds a Czech QR Platba SPD string, matching Python's qr_code handler.
 // Invalid account falls back to defaultAccount.
 // Amount is clamped to [0, 10_000_000]; non-numeric input becomes "0.00".
 // Message is truncated to 60 runes and stripped of '*' characters.
 func BuildSPD(account, amount, message, defaultAccount string) string {
 	if !validAccount.MatchString(account) {
 		account = defaultAccount
 	}
 	var amtStr string
 	var f float64
 	if _, err := fmt.Sscanf(amount, "%f", &f); err != nil || f < 0 || f > 10_000_000 {
 		amtStr = "0.00"
 	} else {
 		amtStr = fmt.Sprintf("%.2f", f)
 	}
 	if utf8.RuneCountInString(message) > 60 {
 		runes := []rune(message)
 		message = string(runes[:60])
 	}
 	message = strings.ReplaceAll(message, "*", "")
 	var accStr string
 	if parts := strings.SplitN(account, "/", 2); len(parts) == 2 {
 		accStr = parts[0] + "*BC:" + parts[1]
 	} else {
 		accStr = account
 	}
 	return fmt.Sprintf("SPD*1.0*ACC:%s*AM:%s*CC:CZK*MSG:%s", accStr, amtStr, message)
 }
 // RenderQRCode encodes payload as a PNG QR code (256×256, error correction Medium).
 func RenderQRCode(payload string) ([]byte, error) {
 	return qrcode.Encode(payload, qrcode.Medium, 256)
 }
--- a/go/internal/web/qr_test.go
+++ b/go/internal/web/qr_test.go
@@ -0,0 +1,91 @@
 package web
 import (
 	"strings"
 	"testing"
 )
 func TestQRBuildSPD(t *testing.T) {
 	const def = "2702008874/2010"
 	cases := []struct {
 		name    string
 		account string
 		amount  string
 		message string
 		want    string
 	}{
 		{
 			name:    "czech account",
 			account: "2702008874/2010",
 			amount:  "700",
 			message: "Test Member: 01/2026",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:700.00*CC:CZK*MSG:Test Member: 01/2026",
 		},
 		{
 			name:    "IBAN account",
 			account: "CZ6508000000192000145399",
 			amount:  "500",
 			message: "hi",
 			want:    "SPD*1.0*ACC:CZ6508000000192000145399*AM:500.00*CC:CZK*MSG:hi",
 		},
 		{
 			name:    "invalid account falls back to default",
 			account: "NOTANACCOUNT",
 			amount:  "100",
 			message: "x",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:100.00*CC:CZK*MSG:x",
 		},
 		{
 			name:    "empty account falls back to default",
 			account: "",
 			amount:  "0",
 			message: "",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:0.00*CC:CZK*MSG:",
 		},
 		{
 			name:    "negative amount clamped to 0.00",
 			account: def,
 			amount:  "-1",
 			message: "",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:0.00*CC:CZK*MSG:",
 		},
 		{
 			name:    "amount over 10M clamped to 0.00",
 			account: def,
 			amount:  "99999999",
 			message: "",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:0.00*CC:CZK*MSG:",
 		},
 		{
 			name:    "non-numeric amount becomes 0.00",
 			account: def,
 			amount:  "abc",
 			message: "",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:0.00*CC:CZK*MSG:",
 		},
 		{
 			name:    "asterisks stripped from message",
 			account: def,
 			amount:  "100",
 			message: "pay*now",
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:100.00*CC:CZK*MSG:paynow",
 		},
 		{
 			name:    "message truncated to 60 runes",
 			account: def,
 			amount:  "0",
 			message: strings.Repeat("á", 65),
 			want:    "SPD*1.0*ACC:2702008874*BC:2010*AM:0.00*CC:CZK*MSG:" + strings.Repeat("á", 60),
 		},
 	}
 	for _, tc := range cases {
 		t.Run(tc.name, func(t *testing.T) {
 			got := BuildSPD(tc.account, tc.amount, tc.message, def)
 			if got != tc.want {
 				t.Errorf("\ngot:  %s\nwant: %s", got, tc.want)
 			}
 		})
 	}
 }
--- a/go/internal/web/render.go
+++ b/go/internal/web/render.go
@@ -6,8 +6,6 @@ import (
 	"html/template"
 	"log/slog"
 	"net/http"
 	"net/url"
 	"strconv"
 )
 // PageData is the view model passed to every HTML template.
@@ -23,6 +21,34 @@ type AdultsPageData struct {
 	Error string
 }
 // JuniorsPageData is the view model for the /juniors HTML page.
 type JuniorsPageData struct {
 	PageData
 	Data  api.JuniorsResponse
 	Error string
 }
 // PaymentsPageData is the view model for the /payments HTML page.
 type PaymentsPageData struct {
 	PageData
 	Data  api.PaymentsResponse
 	Error string
 }
 // SyncPageData is the view model for the /sync-bank HTML page.
 type SyncPageData struct {
 	PageData
 	Output  string
 	Success bool
 }
 // FlushPageData is the view model for the /flush-cache HTML page.
 type FlushPageData struct {
 	PageData
 	Flushed bool
 	Deleted int
 }
 // Renderer parses and executes HTML templates from the embedded FS.
 type Renderer struct {
 	tmpls map[string]*template.Template
@@ -30,36 +56,7 @@ type Renderer struct {
 var pageNames = []string{"adults", "juniors", "payments", "sync", "flush_cache"}
-// qrHref builds the /qr query URL for a single-month Pay button.
+var tmplFuncs = template.FuncMap{}
 // rawMonth is "YYYY-MM"; it is converted to "MM/YYYY" in the QR message.
 func qrHref(account string, amount int, name, rawMonth string) string {
 	// Convert "YYYY-MM" → "MM/YYYY" to match Python's showPayQR JS.
 	if len(rawMonth) == 7 && rawMonth[4] == '-' {
 		rawMonth = rawMonth[5:] + "/" + rawMonth[:4]
 	}
 	msg := name + ": " + rawMonth
 	return "/qr?" + url.Values{
 		"account": {account},
 		"amount":  {strconv.Itoa(amount)},
 		"message": {msg},
 	}.Encode()
 }
 // qrHrefAll builds the /qr query URL for a Pay-All button.
 // rawPeriods is the "+" -joined MM/YYYY string from MemberRow.RawUnpaidPeriods.
 func qrHrefAll(account string, amount int, name, rawPeriods string) string {
 	msg := name + ": " + rawPeriods
 	return "/qr?" + url.Values{
 		"account": {account},
 		"amount":  {strconv.Itoa(amount)},
 		"message": {msg},
 	}.Encode()
 }
 var tmplFuncs = template.FuncMap{
 	"qrHref":    qrHref,
 	"qrHrefAll": qrHrefAll,
 }
 // NewRenderer parses all templates from the embedded FS.
 // A parse failure should be treated as a startup-time fatal error.
--- a/go/internal/web/server.go
+++ b/go/internal/web/server.go
@@ -1,11 +1,13 @@
 package web
 import (
 	"context"
 	"fmt"
 	"fuj-management/go/internal/config"
 	"fuj-management/go/internal/services/membership"
 	"fuj-management/go/internal/web/api"
 	"fuj-management/go/internal/web/middleware"
 	"io"
 	"io/fs"
 	"log/slog"
 	"net/http"
@@ -18,8 +20,16 @@ type BuildInfo struct {
 	BuildDate string
 }
 // ActionHandlers holds function closures for side-effectful operations that
 // require dependencies (fio, sheets) not present on the core API handler.
 type ActionHandlers struct {
 	// BankSync runs sync+infer and writes a human-readable log to out.
 	// nil disables the /sync-bank action (renders an error instead).
 	BankSync func(ctx context.Context, out io.Writer) error
 }
 // Run registers routes and starts the HTTP server on addr.
-func Run(logger *slog.Logger, addr string, build BuildInfo, sources membership.Sources, cfg config.Config) error {
+func Run(logger *slog.Logger, addr string, build BuildInfo, sources membership.Sources, cfg config.Config, actions ActionHandlers) error {
 	renderer, err := NewRenderer()
 	if err != nil {
 		return fmt.Errorf("init templates: %w", err)
@@ -33,7 +43,7 @@ func Run(logger *slog.Logger, addr string, build BuildInfo, sources membership.S
 		Config:       cfg,
 		Logger:       logger,
 	}
-	hh := NewHTMLHandler(renderer, build, ah)
+	hh := NewHTMLHandler(renderer, build, ah, actions)
 	staticSubFS, err := fs.Sub(staticFS, "static")
 	if err != nil {
@@ -50,13 +60,16 @@ func Run(logger *slog.Logger, addr string, build BuildInfo, sources membership.S
 	mux.HandleFunc("GET /juniors", hh.ServeJuniors)
 	mux.HandleFunc("GET /payments", hh.ServePayments)
 	mux.HandleFunc("GET /sync-bank", hh.ServeSync)
-	mux.HandleFunc("GET /flush-cache", hh.ServeFlushCache)
+	mux.HandleFunc("GET /flush-cache", hh.ServeFlushCacheGET)
 	mux.HandleFunc("POST /flush-cache", hh.ServeFlushCachePOST)
 	mux.HandleFunc("GET /qr", hh.ServeQR)
 	// Static files
 	mux.Handle("/static/", http.StripPrefix("/static/", http.FileServerFS(staticSubFS)))
 	// JSON API routes
 	mux.HandleFunc("GET /api/version", ah.ServeVersion)
 	mux.HandleFunc("GET /version", ah.ServeVersion)
 	mux.HandleFunc("GET /api/adults", ah.ServeAdults)
 	mux.HandleFunc("GET /api/juniors", ah.ServeJuniors)
 	mux.HandleFunc("GET /api/payments", ah.ServePayments)
--- a/go/internal/web/static/css/app.css
+++ b/go/internal/web/static/css/app.css
@@ -442,6 +442,23 @@ tr:hover {
 }
 /* QR Modal styles */
 #qrModal {
    display: none !important;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.9);
    z-index: 9999;
    justify-content: center;
    align-items: center;
 }
 #qrModal.active {
    display: flex !important;
 }
 #qrModal .modal-content {
    max-width: 400px;
    text-align: center;
@@ -476,3 +493,59 @@ tr:hover {
    color: #00ff00;
    font-family: monospace;
 }
 /* /payments ledger */
 .ledger-container {
    width: 100%;
    max-width: 1000px;
    margin-bottom: 40px;
 }
 .member-block {
    margin-bottom: 20px;
 }
 .txn-table {
    border-collapse: collapse;
    width: 100%;
    margin-top: 5px;
 }
 .txn-table th,
 .txn-table td {
    padding: 2px 8px;
    text-align: left;
    border-bottom: 1px dashed #222;
 }
 .txn-table th {
    color: #555;
    text-transform: lowercase;
    font-weight: normal;
    border-bottom: 1px solid #333;
 }
 .txn-date {
    min-width: 80px;
    color: #888;
 }
 .txn-amount {
    min-width: 80px;
    text-align: right !important;
    color: #00ff00;
 }
 .txn-purpose {
    min-width: 100px;
    color: #aaa;
 }
 .txn-message {
    color: #666;
    font-style: italic;
 }
 .txn-table tr:hover {
    background-color: #1a1a1a;
 }
--- a/go/internal/web/static/js/member-detail.js
+++ b/go/internal/web/static/js/member-detail.js
@@ -0,0 +1,245 @@
 // Member-detail modal for /adults and /juniors pages.
 // Fetches /api/<page> once on load, caches the response, renders on row click.
 // Mirrors templates/adults.html JS (lines 718-993) but as a standalone module.
 (function () {
  'use strict';
  const container = document.getElementById('filterContainer');
  if (!container) return;
  const page = container.dataset.page; // "adults" | "juniors"
  if (!page) return;
  let apiData = null;
  let currentMemberName = null;
  // ── Data load ─────────────────────────────────────────────────────────────
  async function loadData() {
    if (apiData) return apiData;
    const r = await fetch('/api/' + page);
    if (!r.ok) throw new Error('[member-detail] failed to fetch /api/' + page + ': ' + r.status);
    apiData = await r.json();
    return apiData;
  }
  // Pre-warm on page load so first click is instant.
  loadData().catch(function (err) { console.error(err); });
  // ── Modal render ──────────────────────────────────────────────────────────
  async function showMember(name) {
    currentMemberName = name;
    const data = (await loadData());
    const member = data.member_data[name];
    if (!member) return;
    document.getElementById('modalMemberName').textContent = name;
    document.getElementById('modalTier').textContent = 'Tier: ' + (member.tier || '-');
    const monthLabels = data.month_labels || {};
    const statusBody = document.getElementById('modalStatusBody');
    statusBody.innerHTML = '';
    const allTransactions = [];
    const monthKeys = Object.keys(member.months || {}).sort().reverse();
    monthKeys.forEach(function (m) {
      const md = member.months[m];
      const expected = md.expected;          // int for adults; int or "?" for juniors
      const paid = md.paid || 0;
      const attendance = md.attendance_count || 0;
      const originalExpected = md.original_expected;
      const isUnknown = (expected === '?');
      let status = '-';
      let statusClass = '';
      if (!isUnknown && (expected > 0 || paid > 0)) {
        if (paid >= expected && expected > 0) {
          status = paid + '/' + expected;
          statusClass = 'cell-ok';
        } else if (paid > 0) {
          status = paid + '/' + expected;
        } else {
          status = '0/' + expected;
          statusClass = 'cell-unpaid';
        }
      } else if (isUnknown) {
        status = paid > 0 ? paid + '/?' : '?';
      }
      let expectedCell;
      if (isUnknown) {
        expectedCell = '?';
      } else if (md.exception) {
        expectedCell = '<span style="color: #ffaa00;" title="Overridden from ' + originalExpected + '">' + expected + '*</span>';
      } else {
        expectedCell = expected;
      }
      const displayMonth = monthLabels[m] || m;
      const row = document.createElement('tr');
      row.innerHTML =
        '<td style="color: #888;">' + displayMonth + '</td>' +
        '<td style="text-align: center; color: #ccc;">' + attendance + '</td>' +
        '<td style="text-align: center; color: #ccc;">' + expectedCell + '</td>' +
        '<td style="text-align: center; color: #ccc;">' + paid + '</td>' +
        '<td style="text-align: right;" class="' + statusClass + '">' + status + '</td>';
      statusBody.appendChild(row);
      if (md.transactions) {
        md.transactions.forEach(function (tx) {
          allTransactions.push(Object.assign({ month: m }, tx));
        });
      }
    });
    // Exceptions
    const exList = document.getElementById('modalExceptionList');
    const exSection = document.getElementById('modalExceptionSection');
    exList.innerHTML = '';
    const exceptions = [];
    monthKeys.forEach(function (m) {
      if (member.months[m].exception) {
        exceptions.push(Object.assign({ month: m }, member.months[m].exception));
      }
    });
    if (exceptions.length > 0) {
      exSection.style.display = 'block';
      exceptions.forEach(function (ex) {
        const displayMonth = monthLabels[ex.month] || ex.month;
        const item = document.createElement('div');
        item.className = 'tx-item';
        item.innerHTML =
          '<div class="tx-meta">' + displayMonth + '</div>' +
          '<div class="tx-main"><span class="tx-amount" style="color: #ffaa00;">' + ex.amount + ' CZK</span></div>' +
          '<div class="tx-msg">' + (ex.note || 'No details provided.') + '</div>';
        exList.appendChild(item);
      });
    } else {
      exSection.style.display = 'none';
    }
    // Other transactions
    const otherList = document.getElementById('modalOtherList');
    const otherSection = document.getElementById('modalOtherSection');
    otherList.innerHTML = '';
    if (member.other_transactions && member.other_transactions.length > 0) {
      otherSection.style.display = 'block';
      member.other_transactions.forEach(function (tx) {
        const item = document.createElement('div');
        item.className = 'tx-item';
        item.innerHTML =
          '<div class="tx-meta">' + tx.date + ' | ' + (tx.purpose || 'Other') + '</div>' +
          '<div class="tx-main">' +
            '<span class="tx-amount" style="color: #66ccff;">' + tx.amount + ' CZK</span>' +
            '<span class="tx-sender">' + (tx.sender || '') + '</span>' +
          '</div>' +
          '<div class="tx-msg">' + (tx.message || '') + '</div>';
        otherList.appendChild(item);
      });
    } else {
      otherSection.style.display = 'none';
    }
    // Matched transactions (payment history)
    const txList = document.getElementById('modalTxList');
    txList.innerHTML = '';
    if (allTransactions.length === 0) {
      txList.innerHTML = '<div style="color: #444; font-style: italic; padding: 10px 0;">No transactions matched to this member.</div>';
    } else {
      allTransactions.sort(function (a, b) { return b.date.localeCompare(a.date); });
      allTransactions.forEach(function (tx) {
        const displayMonth = monthLabels[tx.month] || tx.month;
        const item = document.createElement('div');
        item.className = 'tx-item';
        item.innerHTML =
          '<div class="tx-meta">' + tx.date + ' | matched to ' + displayMonth + '</div>' +
          '<div class="tx-main">' +
            '<span class="tx-amount">' + tx.amount + ' CZK</span>' +
            '<span class="tx-sender">' + (tx.sender || '') + '</span>' +
          '</div>' +
          '<div class="tx-msg">' + (tx.message || '') + '</div>';
        txList.appendChild(item);
      });
    }
    // Raw payments — hidden by default; reset toggle on each open
    const rawList = document.getElementById('modalRawList');
    const rawToggle = document.getElementById('rawPaymentsToggle');
    rawList.style.display = 'none';
    rawToggle.textContent = '[show]';
    rawList.innerHTML = '';
    const rawRows = (data.raw_payments || {})[name] || [];
    if (rawRows.length === 0) {
      rawList.innerHTML = '<div style="color: #444; font-style: italic; padding: 10px 0;">No raw payments tied to this member.</div>';
    } else {
      rawRows.forEach(function (tx) {
        const inferredNote = (tx.inferred_amount && tx.inferred_amount !== '' && tx.inferred_amount !== tx.amount)
          ? ' <span style="color:#888;">(inferred: ' + tx.inferred_amount + ')</span>'
          : '';
        const manualNote = tx.manual_fix ? ' <span style="color:#ffaa00;">[manual fix]</span>' : '';
        const bankIdNote = tx.bank_id ? '<span style="color:#444;"> · bank_id: ' + tx.bank_id + '</span>' : '';
        const item = document.createElement('div');
        item.className = 'tx-item';
        item.innerHTML =
          '<div class="tx-meta">' + tx.date + ' | purpose: ' + (tx.purpose || '—') + manualNote + '</div>' +
          '<div class="tx-main">' +
            '<span class="tx-amount">' + tx.amount + ' CZK' + inferredNote + '</span>' +
            '<span class="tx-sender">' + (tx.sender || '') + '</span>' +
          '</div>' +
          '<div class="tx-msg">' + (tx.message || '') + '</div>' +
          '<div class="tx-meta">' + (tx.person || '') + bankIdNote + '</div>';
        rawList.appendChild(item);
      });
    }
    document.getElementById('memberModal').classList.add('active');
  }
  // ── Raw-payments toggle ───────────────────────────────────────────────────
  function toggleRawPayments(ev) {
    ev.preventDefault();
    const list = document.getElementById('modalRawList');
    const link = document.getElementById('rawPaymentsToggle');
    const hidden = list.style.display === 'none';
    list.style.display = hidden ? 'block' : 'none';
    link.textContent = hidden ? '[hide]' : '[show]';
  }
  // ── Close + keyboard nav ──────────────────────────────────────────────────
  function closeModal() {
    document.getElementById('memberModal').classList.remove('active');
  }
  function navigateMember(direction) {
    const rows = Array.from(document.querySelectorAll('tr.member-row'));
    const visible = rows.filter(function (r) { return r.style.display !== 'none'; });
    const idx = visible.findIndex(function (r) { return r.dataset.name === currentMemberName; });
    if (idx === -1) return;
    const next = idx + direction;
    if (next >= 0 && next < visible.length) {
      showMember(visible[next].dataset.name);
    }
  }
  // ── Wiring ────────────────────────────────────────────────────────────────
  document.querySelectorAll('.info-icon[data-name]').forEach(function (el) {
    el.addEventListener('click', function (ev) {
      ev.stopPropagation();
      showMember(el.dataset.name);
    });
  });
  document.getElementById('rawPaymentsToggle').addEventListener('click', toggleRawPayments);
  document.addEventListener('keydown', function (e) {
    if (e.key === 'Escape') { closeModal(); return; }
    const modal = document.getElementById('memberModal');
    if (!modal.classList.contains('active')) return;
    if (e.key === 'ArrowDown') { e.preventDefault(); navigateMember(1); }
    if (e.key === 'ArrowUp')   { e.preventDefault(); navigateMember(-1); }
  });
 }());
--- a/go/internal/web/static/js/payment-qr.js
+++ b/go/internal/web/static/js/payment-qr.js
@@ -0,0 +1,60 @@
 (function () {
  'use strict';
  const container = document.getElementById('filterContainer');
  if (!container) return;
  const bankAccount = container.dataset.bankAccount || '';
  const modal     = document.getElementById('qrModal');
  const titleEl   = document.getElementById('qrTitle');
  const imgEl     = document.getElementById('qrImg');
  const accountEl = document.getElementById('qrAccount');
  const amountEl  = document.getElementById('qrAmount');
  const messageEl = document.getElementById('qrMessage');
  if (!modal || !titleEl || !imgEl || !accountEl || !amountEl || !messageEl) return;
  // Convert "YYYY-MM" → "MM/YYYY"; "+"-joined ranges converted piece-wise.
  // Mirrors templates/adults.html showPayQR logic.
  function toCzechMonth(rawMonth) {
    return rawMonth.split('+')
      .map(function (p) { return p.replace(/^(\d{4})-(\d{2})$/, '$2/$1'); })
      .join('+');
  }
  function showQR(name, amount, month, rawMonth) {
    var numericMonth = toCzechMonth(rawMonth);
    var message = name + ': ' + numericMonth;
    titleEl.innerText   = 'Payment for ' + month;
    accountEl.innerText = bankAccount;
    amountEl.innerText  = amount;
    messageEl.innerText = message;
    imgEl.src = '/qr?'
      + 'account=' + encodeURIComponent(bankAccount)
      + '&amount=' + encodeURIComponent(amount)
      + '&message=' + encodeURIComponent(message);
    modal.classList.add('active');
  }
  function closeQR() {
    modal.classList.remove('active');
  }
  document.addEventListener('click', function (ev) {
    var btn = ev.target.closest('.pay-btn');
    if (!btn) return;
    ev.preventDefault();
    showQR(
      btn.dataset.name,
      btn.dataset.amount,
      btn.dataset.month,
      btn.dataset.rawMonth
    );
  });
  document.addEventListener('keydown', function (e) {
    if (e.key === 'Escape' && modal.classList.contains('active')) closeQR();
  });
 }());
--- a/go/internal/web/templates/adults.tmpl
+++ b/go/internal/web/templates/adults.tmpl
@@ -12,7 +12,7 @@
  <a href="{{.Data.PaymentsURL}}" target="_blank" rel="noopener">Payments Ledger</a>
 </div>
-<div class="filter-container" id="filterContainer" data-current-month="{{.Data.CurrentMonth}}">
+<div class="filter-container" id="filterContainer" data-current-month="{{.Data.CurrentMonth}}" data-page="adults" data-bank-account="{{.Data.BankAccount}}">
  <div class="filter-item">
    <label class="filter-label" for="nameFilter">Member</label>
    <input id="nameFilter" class="filter-input" type="text" placeholder="Filter by name…">
@@ -56,20 +56,20 @@
  <tbody>
    {{range $row := .Data.Results}}
    <tr class="member-row" data-name="{{$row.Name}}">
-      <td class="member-name">{{$row.Name}}</td>
+      <td class="member-name">{{$row.Name}}<span class="info-icon" data-name="{{$row.Name}}" title="Show details">[i]</span></td>
      {{range $i, $cell := $row.Months}}
      <td data-month-idx="{{$i}}" title="{{$cell.Tooltip}}"
          class="{{if eq $cell.Status "empty"}}cell-empty{{else if and (or (eq $cell.Status "unpaid") (eq $cell.Status "partial")) (ge $cell.RawMonth $.Data.CurrentMonth)}}cell-unpaid-current{{else if or (eq $cell.Status "unpaid") (eq $cell.Status "partial")}}cell-unpaid{{else if eq $cell.Status "ok"}}cell-ok{{end}}{{if $cell.Overridden}} cell-overridden{{end}}">
        {{$cell.Text}}
        {{if and (or (eq $cell.Status "unpaid") (eq $cell.Status "partial")) (lt $cell.RawMonth $.Data.CurrentMonth)}}
-        <a class="pay-btn" href="{{qrHref $.Data.BankAccount $cell.Amount $row.Name $cell.RawMonth}}">Pay</a>
+        <button type="button" class="pay-btn" data-name="{{$row.Name}}" data-amount="{{$cell.Amount}}" data-month="{{$cell.Month}}" data-raw-month="{{$cell.RawMonth}}">Pay</button>
        {{end}}
      </td>
      {{end}}
      <td class="{{if lt $row.Balance 0}}balance-neg{{else if gt $row.Balance 0}}balance-pos{{end}}" style="position: relative;">
        {{$row.Balance}}
        {{if gt $row.PayableAmount 0}}
-        <a class="pay-btn" href="{{qrHrefAll $.Data.BankAccount $row.PayableAmount $row.Name $row.RawUnpaidPeriods}}">Pay All</a>
+        <button type="button" class="pay-btn" data-name="{{$row.Name}}" data-amount="{{$row.PayableAmount}}" data-month="{{$row.UnpaidPeriods}}" data-raw-month="{{$row.RawUnpaidPeriods}}" data-pay-all="1">Pay All</button>
        {{end}}
      </td>
    </tr>
@@ -137,5 +137,71 @@
 {{end}}
 <div id="memberModal" onclick="if(event.target===this)this.classList.remove('active')">
  <div class="modal-content">
    <div class="modal-header">
      <div class="modal-title" id="modalMemberName">Member Name</div>
      <div class="close-btn" onclick="document.getElementById('memberModal').classList.remove('active')">[close]</div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">Status Summary</div>
      <div id="modalTier" style="margin-bottom: 10px; color: #888;">Tier: -</div>
      <table class="modal-table">
        <thead><tr>
          <th>Month</th>
          <th style="text-align: center;">Att.</th>
          <th style="text-align: center;">Expected</th>
          <th style="text-align: center;">Paid</th>
          <th style="text-align: right;">Status</th>
        </tr></thead>
        <tbody id="modalStatusBody"></tbody>
      </table>
    </div>
    <div class="modal-section" id="modalExceptionSection" style="display: none;">
      <div class="modal-section-title">Fee Exceptions</div>
      <div id="modalExceptionList" class="tx-list"></div>
    </div>
    <div class="modal-section" id="modalOtherSection" style="display: none;">
      <div class="modal-section-title">Other Transactions</div>
      <div id="modalOtherList" class="tx-list"></div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">Payment History</div>
      <div id="modalTxList" class="tx-list"></div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">
        Raw Payments
        <a href="#" id="rawPaymentsToggle" class="raw-toggle">[show]</a>
      </div>
      <div id="modalRawList" class="tx-list" style="display: none;"></div>
    </div>
  </div>
 </div>
 <div id="qrModal" onclick="if(event.target===this)this.classList.remove('active')">
  <div class="modal-content">
    <div class="modal-header">
      <div class="modal-title" id="qrTitle">Payment for —</div>
      <div class="close-btn" onclick="document.getElementById('qrModal').classList.remove('active')">[close]</div>
    </div>
    <div class="qr-image">
      <img id="qrImg" src="" alt="Payment QR Code">
    </div>
    <div class="qr-details">
      <div>Account: <span id="qrAccount"></span></div>
      <div>Amount: <span id="qrAmount"></span> CZK</div>
      <div>Message: <span id="qrMessage"></span></div>
    </div>
  </div>
 </div>
 <script src="/static/js/filters.js" defer></script>
 <script src="/static/js/member-detail.js" defer></script>
 <script src="/static/js/payment-qr.js" defer></script>
 {{end}}
--- a/go/internal/web/templates/flush_cache.tmpl
+++ b/go/internal/web/templates/flush_cache.tmpl
@@ -1,5 +1,11 @@
 {{define "title"}}Flush Cache{{end}}
 {{define "content"}}
 <h1>Flush Cache</h1>
-<p class="description">Coming in M6.6</p>
+{{if .Flushed}}
  <p class="status-ok">Cache flushed: {{.Deleted}} file(s) deleted.</p>
 {{end}}
 <p class="description">Deletes all cached data files so the next request fetches fresh data from Google Sheets.</p>
 <form method="POST" action="/flush-cache">
  <button type="submit" class="btn">Flush Cache</button>
 </form>
 {{end}}
--- a/go/internal/web/templates/juniors.tmpl
+++ b/go/internal/web/templates/juniors.tmpl
@@ -1,5 +1,187 @@
 {{define "title"}}Juniors{{end}}
 {{define "content"}}
 <h1>Juniors Dashboard</h1>
-<p class="description">Coming in M6.3</p>
+
 {{if .Error}}
 <div class="description">Error loading data: {{.Error}}</div>
 {{else}}
 <div class="description">
  Balances calculated by matching Google Sheet payments against attendance fees.<br>
  Source: <a href="{{.Data.AttendanceURL}}" target="_blank" rel="noopener">Attendance Sheet</a> |
  <a href="{{.Data.PaymentsURL}}" target="_blank" rel="noopener">Payments Ledger</a>
 </div>
 <div class="filter-container" id="filterContainer" data-current-month="{{.Data.CurrentMonth}}" data-page="juniors" data-bank-account="{{.Data.BankAccount}}">
  <div class="filter-item">
    <label class="filter-label" for="nameFilter">Member</label>
    <input id="nameFilter" class="filter-input" type="text" placeholder="Filter by name…">
  </div>
  <div class="filter-item">
    <label class="filter-label" for="fromMonth">From</label>
    <select id="fromMonth" class="filter-select">
      <option value="">All</option>
      {{range $i, $m := .Data.Months}}
      <option value="{{$i}}">{{$m}}</option>
      {{end}}
    </select>
  </div>
  <div class="filter-item">
    <label class="filter-label" for="toMonth">To</label>
    <select id="toMonth" class="filter-select">
      <option value="">All</option>
      {{range $i, $m := .Data.Months}}
      <option value="{{$i}}">{{$m}}</option>
      {{end}}
    </select>
  </div>
  <div class="filter-item">
    <button id="applyFilter" class="filter-select" type="button" style="cursor: pointer;">Apply</button>
    <button id="clearFilter" class="filter-select" type="button" style="cursor: pointer;">All</button>
  </div>
 </div>
 {{if .Data.Results}}
 <div class="table-container">
 <table>
  <thead>
    <tr>
      <th>Member</th>
      {{range $i, $m := .Data.Months}}
      <th data-month-idx="{{$i}}" data-raw-month="{{index $.Data.RawMonths $i}}">{{$m}}</th>
      {{end}}
      <th>Balance</th>
    </tr>
  </thead>
  <tbody>
    {{range $row := .Data.Results}}
    <tr class="member-row" data-name="{{$row.Name}}">
      <td class="member-name">{{$row.Name}}<span class="info-icon" data-name="{{$row.Name}}" title="Show details">[i]</span></td>
      {{range $i, $cell := $row.Months}}
      <td data-month-idx="{{$i}}" title="{{$cell.Tooltip}}"
          class="{{if eq $cell.Status "empty"}}cell-empty{{else if and (or (eq $cell.Status "unpaid") (eq $cell.Status "partial")) (ge $cell.RawMonth $.Data.CurrentMonth)}}cell-unpaid-current{{else if or (eq $cell.Status "unpaid") (eq $cell.Status "partial")}}cell-unpaid{{else if eq $cell.Status "ok"}}cell-ok{{end}}{{if $cell.Overridden}} cell-overridden{{end}}">
        {{$cell.Text}}
        {{if and (or (eq $cell.Status "unpaid") (eq $cell.Status "partial")) (lt $cell.RawMonth $.Data.CurrentMonth)}}
        <button type="button" class="pay-btn" data-name="{{$row.Name}}" data-amount="{{$cell.Amount}}" data-month="{{$cell.Month}}" data-raw-month="{{$cell.RawMonth}}">Pay</button>
        {{end}}
      </td>
      {{end}}
      <td class="{{if lt $row.Balance 0}}balance-neg{{else if gt $row.Balance 0}}balance-pos{{end}}" style="position: relative;">
        {{$row.Balance}}
        {{if gt $row.PayableAmount 0}}
        <button type="button" class="pay-btn" data-name="{{$row.Name}}" data-amount="{{$row.PayableAmount}}" data-month="{{$row.UnpaidPeriods}}" data-raw-month="{{$row.RawUnpaidPeriods}}" data-pay-all="1">Pay All</button>
        {{end}}
      </td>
    </tr>
    {{end}}
    <tr class="totals-row" style="font-weight: bold; background-color: #111; border-top: 2px solid #333;">
      <td style="text-align: left; padding: 6px 8px;">TOTAL</td>
      {{range $i, $t := .Data.Totals}}
      <td data-month-idx="{{$i}}" data-raw-month="{{index $.Data.RawMonths $i}}" class="{{if eq $t.Status "ok"}}cell-ok{{else if eq $t.Status "unpaid"}}cell-unpaid{{else if eq $t.Status "surplus"}}cell-overridden{{end}}" style="padding-top: 4px; padding-bottom: 4px;">
        <span style="font-size: 0.6em; font-weight: normal; color: #666; text-transform: lowercase; display: block; margin-bottom: 2px;">received / expected</span>
        {{$t.Text}}
      </td>
      {{end}}
      <td></td>
    </tr>
  </tbody>
 </table>
 </div>
 {{else}}
 <div class="description">No members found.</div>
 {{end}}
 {{if .Data.Credits}}
 <h2>Credits (Advance Payments / Surplus)</h2>
 <div class="list-container">
  {{range .Data.Credits}}
  <div class="list-item">
    <span class="list-item-name">{{.Name}}</span>
    <span class="list-item-val">{{.Amount}} CZK</span>
  </div>
  {{end}}
 </div>
 {{end}}
 {{if .Data.Debts}}
 <h2>Debts (Missing Payments)</h2>
 <div class="list-container">
  {{range .Data.Debts}}
  <div class="list-item">
    <span class="list-item-name">{{.Name}}</span>
    <span class="list-item-val" style="color: #ff3333;">{{.Amount}} CZK</span>
  </div>
  {{end}}
 </div>
 {{end}}
 {{end}}
 <div id="memberModal" onclick="if(event.target===this)this.classList.remove('active')">
  <div class="modal-content">
    <div class="modal-header">
      <div class="modal-title" id="modalMemberName">Member Name</div>
      <div class="close-btn" onclick="document.getElementById('memberModal').classList.remove('active')">[close]</div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">Status Summary</div>
      <div id="modalTier" style="margin-bottom: 10px; color: #888;">Tier: -</div>
      <table class="modal-table">
        <thead><tr>
          <th>Month</th>
          <th style="text-align: center;">Att.</th>
          <th style="text-align: center;">Expected</th>
          <th style="text-align: center;">Paid</th>
          <th style="text-align: right;">Status</th>
        </tr></thead>
        <tbody id="modalStatusBody"></tbody>
      </table>
    </div>
    <div class="modal-section" id="modalExceptionSection" style="display: none;">
      <div class="modal-section-title">Fee Exceptions</div>
      <div id="modalExceptionList" class="tx-list"></div>
    </div>
    <div class="modal-section" id="modalOtherSection" style="display: none;">
      <div class="modal-section-title">Other Transactions</div>
      <div id="modalOtherList" class="tx-list"></div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">Payment History</div>
      <div id="modalTxList" class="tx-list"></div>
    </div>
    <div class="modal-section">
      <div class="modal-section-title">
        Raw Payments
        <a href="#" id="rawPaymentsToggle" class="raw-toggle">[show]</a>
      </div>
      <div id="modalRawList" class="tx-list" style="display: none;"></div>
    </div>
  </div>
 </div>
 <div id="qrModal" onclick="if(event.target===this)this.classList.remove('active')">
  <div class="modal-content">
    <div class="modal-header">
      <div class="modal-title" id="qrTitle">Payment for —</div>
      <div class="close-btn" onclick="document.getElementById('qrModal').classList.remove('active')">[close]</div>
    </div>
    <div class="qr-image">
      <img id="qrImg" src="" alt="Payment QR Code">
    </div>
    <div class="qr-details">
      <div>Account: <span id="qrAccount"></span></div>
      <div>Amount: <span id="qrAmount"></span> CZK</div>
      <div>Message: <span id="qrMessage"></span></div>
    </div>
  </div>
 </div>
 <script src="/static/js/filters.js" defer></script>
 <script src="/static/js/member-detail.js" defer></script>
 <script src="/static/js/payment-qr.js" defer></script>
 {{end}}
--- a/go/internal/web/templates/payments.tmpl
+++ b/go/internal/web/templates/payments.tmpl
@@ -1,5 +1,38 @@
 {{define "title"}}Payments Ledger{{end}}
 {{define "content"}}
 <h1>Payments Ledger</h1>
-<p class="description">Coming in M6.4</p>
+<p class="description">
    All bank transactions from the
    <a href="{{.Data.PaymentsURL}}" target="_blank">payments sheet</a>,
    grouped by member. Names are matched against the
    <a href="{{.Data.AttendanceURL}}" target="_blank">attendance sheet</a>.
 </p>
 {{if .Error}}<p class="error">{{.Error}}</p>{{end}}
 <div class="ledger-container">
 {{range $person := .Data.SortedPeople}}
    <div class="member-block">
        <h2>{{$person}}</h2>
        <table class="txn-table">
            <thead>
                <tr>
                    <th class="txn-date">Date</th>
                    <th class="txn-amount">Amount</th>
                    <th class="txn-purpose">Purpose</th>
                    <th class="txn-message">Bank Message</th>
                </tr>
            </thead>
            <tbody>
            {{range $tx := index $.Data.GroupedPayments $person}}
                <tr>
                    <td class="txn-date">{{$tx.Date}}</td>
                    <td class="txn-amount">{{printf "%.0f" $tx.Amount}} CZK</td>
                    <td class="txn-purpose">{{$tx.Purpose}}</td>
                    <td class="txn-message">{{$tx.Message}}</td>
                </tr>
            {{end}}
            </tbody>
        </table>
    </div>
 {{end}}
 </div>
 {{end}}
--- a/go/internal/web/templates/sync.tmpl
+++ b/go/internal/web/templates/sync.tmpl
@@ -1,5 +1,15 @@
 {{define "title"}}Sync Bank Data{{end}}
 {{define "content"}}
 <h1>Sync Bank Data</h1>
-<p class="description">Coming in M6.6</p>
+{{if .Output}}
  {{if .Success}}
    <p class="status-ok">Sync completed successfully.</p>
  {{else}}
    <p class="status-error">Sync failed — see log below.</p>
  {{end}}
  <pre class="sync-log{{if not .Success}} sync-log--error{{end}}">{{.Output}}</pre>
 {{else}}
  <p class="description">Fetches Fio transactions for the current year, infers payment details, and flushes the cache.</p>
 {{end}}
 <p><a href="/sync-bank" class="btn">{{if .Output}}Run Again{{else}}Run Sync{{end}}</a></p>
 {{end}}
--- a/go/tests/fixtures/reconcile/03_proportional_remainder.json
+++ b/go/tests/fixtures/reconcile/03_proportional_remainder.json
@@ -1,7 +1,7 @@
 {
  "case": "03_proportional_remainder",
  "func": "scripts.match_payments.reconcile",
-  "captured_at": "2026-05-06",
+  "captured_at": "2026-05-11",
  "input": {
    "members": [
      {
@@ -54,10 +54,10 @@
            "original_expected": 750,
            "attendance_count": 3,
            "exception": null,
-            "paid": 324.3243243243243,
+            "paid": 750.0,
            "transactions": [
              {
-                "amount": 324.3243243243243,
+                "amount": 750.0,
                "date": "2026-03-10",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -70,10 +70,10 @@
            "original_expected": 750,
            "attendance_count": 2,
            "exception": null,
-            "paid": 324.3243243243243,
+            "paid": 50.0,
            "transactions": [
              {
-                "amount": 324.3243243243243,
+                "amount": 50.0,
                "date": "2026-03-10",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -86,25 +86,17 @@
            "original_expected": 350,
            "attendance_count": 2,
            "exception": null,
-            "paid": 151.35135135135135,
+            "paid": 0,
-            "transactions": [
+            "transactions": []
              {
                "amount": 151.35135135135135,
                "date": "2026-03-10",
                "sender": "Member_d035d9f9",
                "message": "",
                "confidence": "auto"
              }
            ]
          }
        },
        "other_transactions": [],
-        "total_balance": -1051
+        "total_balance": -1050
      }
    },
    "unmatched": [],
    "credits": {
-      "Member_d035d9f9": -1051
+      "Member_d035d9f9": -1050
    }
  }
 }
--- a/go/tests/fixtures/reconcile/09_multiperson_multimonth.json
+++ b/go/tests/fixtures/reconcile/09_multiperson_multimonth.json
@@ -1,7 +1,7 @@
 {
  "case": "09_multiperson_multimonth",
  "func": "scripts.match_payments.reconcile",
-  "captured_at": "2026-05-06",
+  "captured_at": "2026-05-11",
  "input": {
    "members": [
      {
@@ -63,10 +63,10 @@
            "original_expected": 750,
            "attendance_count": 3,
            "exception": null,
-            "paid": 500.0,
+            "paid": 750.0,
            "transactions": [
              {
-                "amount": 500.0,
+                "amount": 750.0,
                "date": "2026-02-15",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -79,10 +79,10 @@
            "original_expected": 750,
            "attendance_count": 2,
            "exception": null,
-            "paid": 500.0,
+            "paid": 250.0,
            "transactions": [
              {
-                "amount": 500.0,
+                "amount": 250.0,
                "date": "2026-02-15",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -102,10 +102,10 @@
            "original_expected": 750,
            "attendance_count": 2,
            "exception": null,
-            "paid": 681.8181818181819,
+            "paid": 750.0,
            "transactions": [
              {
-                "amount": 681.8181818181819,
+                "amount": 750.0,
                "date": "2026-02-15",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -118,10 +118,10 @@
            "original_expected": 350,
            "attendance_count": 2,
            "exception": null,
-            "paid": 318.18181818181813,
+            "paid": 250.0,
            "transactions": [
              {
-                "amount": 318.18181818181813,
+                "amount": 250.0,
                "date": "2026-02-15",
                "sender": "Member_d035d9f9",
                "message": "",
@@ -131,13 +131,13 @@
          }
        },
        "other_transactions": [],
-        "total_balance": -101
+        "total_balance": -100
      }
    },
    "unmatched": [],
    "credits": {
      "Member_d035d9f9": -500,
-      "Member_f4a93e46": -101
+      "Member_f4a93e46": -100
    }
  }
 }
--- a/scripts/fio_utils.py
+++ b/scripts/fio_utils.py
@@ -4,6 +4,7 @@
 import json
 import os
 import re
 import sys
 import urllib.request
 from datetime import datetime
 from html.parser import HTMLParser
@@ -89,9 +90,11 @@ def parse_czech_amount(s: str) -> float | None:
 def parse_czech_date(s: str) -> str | None:
-    """Parse 'DD.MM.YYYY' to 'YYYY-MM-DD'."""
+    """Parse a Czech date to 'YYYY-MM-DD'. Accepts 4-digit and 2-digit years
    with dot or slash separators; Fio's transparent page mixes 'DD.MM.YYYY'
    and 'DD.MM.YY' in the same response."""
    s = s.strip()
-    for fmt in ("%d.%m.%Y", "%d/%m/%Y"):
+    for fmt in ("%d.%m.%Y", "%d/%m/%Y", "%d.%m.%y", "%d/%m/%y"):
        try:
            return datetime.strptime(s, fmt).strftime("%Y-%m-%d")
        except ValueError:
@@ -146,6 +149,7 @@ def fetch_transactions_transparent(
            "bank_id": "", # HTML scraping doesn't give stable ID
        })
    print(f"fio: transparent fetched {len(rows)} raw rows, {len(transactions)} transaction(s) after filtering", file=sys.stderr)
    return transactions
@@ -169,7 +173,8 @@ def fetch_transactions_api(
    transactions = []
    tx_list = data.get("accountStatement", {}).get("transactionList", {})
-    for tx in (tx_list.get("transaction") or []):
+    raw_list = tx_list.get("transaction") or []
    for tx in raw_list:
        # Each field is {"value": ..., "name": ..., "id": ...} or null
        def val(col_id):
            col = tx.get(f"column{col_id}")
@@ -197,6 +202,7 @@ def fetch_transactions_api(
            "currency": str(val(14) or "CZK"), # column14 = Currency
        })
    print(f"fio: api fetched {len(raw_list)} raw transaction(s), {len(transactions)} after filtering", file=sys.stderr)
    return transactions
@@ -204,8 +210,14 @@ def fetch_transactions(date_from: str, date_to: str) -> list[dict]:
    """Fetch transactions, using API if token available, else transparent page."""
    token = os.environ.get("FIO_API_TOKEN", "").strip()
    if token:
        print(f"fio: using authenticated API, window {date_from}..{date_to}", file=sys.stderr)
        return fetch_transactions_api(token, date_from, date_to)
    print(
        f"fio: using transparent page (FIO_API_TOKEN unset — expect publishing lag), "
        f"window {date_from}..{date_to}, account=2800359168",
        file=sys.stderr,
    )
    # Convert YYYY-MM-DD to DD.MM.YYYY for the transparent page URL
    from_dt = datetime.strptime(date_from, "%Y-%m-%d")
    to_dt = datetime.strptime(date_to, "%Y-%m-%d")
--- a/scripts/match_payments.py
+++ b/scripts/match_payments.py
@@ -468,26 +468,19 @@ def reconcile(
            total_expected = sum(e for _, e in in_window)
-            if total_expected > 0 and in_window_share >= total_expected:
+            if total_expected > 0:
-                # Greedy phase: payment covers all in-window fees; overflow → credit.
+                # Fill-first: iterate in_window in matched_months order (chronological by
-                credits[member_name] = credits.get(member_name, 0) + int(in_window_share - total_expected)
+                # convention from infer_payments.py), allocating min(remaining, deficit) to
-                for m, exp in in_window:
+                # each month. Deficit is net of what prior transactions already paid, so a
-                    alloc = float(exp)
+                # second payment on the same months correctly fills only what remains due.
-                    ledger[member_name][m]["paid"] += alloc
+                # Any surplus after all deficits are covered goes to the credit bucket.
                    ledger[member_name][m]["transactions"].append({
                        "amount": alloc,
                        "date": tx["date"],
                        "sender": tx["sender"],
                        "message": tx["message"],
                        "confidence": confidence,
                    })
            elif total_expected > 0:
                # Proportional phase: distribute in_window_share by each month's expected fee.
                # Last month absorbs any float remainder so the sum equals in_window_share exactly.
                remaining = in_window_share
-                for i, (m, exp) in enumerate(in_window):
+                for m, exp in in_window:
-                    alloc = remaining if i == len(in_window) - 1 else in_window_share * exp / total_expected
+                    paid_so_far = ledger[member_name][m]["paid"]
-                    remaining -= alloc
+                    deficit = max(0.0, float(exp) - paid_so_far)
                    alloc = min(remaining, deficit)
                    if alloc <= 0:
                        continue
                    ledger[member_name][m]["paid"] += alloc
                    ledger[member_name][m]["transactions"].append({
                        "amount": alloc,
@@ -496,6 +489,9 @@ def reconcile(
                        "message": tx["message"],
                        "confidence": confidence,
                    })
                    remaining -= alloc
                if remaining > 0:
                    credits[member_name] = credits.get(member_name, 0) + int(remaining)
            else:
                # Fallback: no expected fees (prepayment before attendance recorded); even split.
                per_month = in_window_share / len(in_window)
--- a/scripts/sync_fio_to_sheets.py
+++ b/scripts/sync_fio_to_sheets.py
@@ -77,6 +77,35 @@ def generate_sync_id(tx: dict) -> str:
    return hashlib.sha256(raw_str.encode("utf-8")).hexdigest()
 def _trunc(s: str, n: int = 40) -> str:
    s = str(s)
    return s if len(s) <= n else s[: n - 1] + "…"
 def _print_fio_table(transactions: list[dict], statuses: list[str]) -> None:
    headers = ["DATE", "AMOUNT", "SENDER", "VS", "MESSAGE", "BANKID", "STATUS"]
    rows = [
        [
            str(tx.get("date", "")),
            f"{float(tx.get('amount', 0)):.2f}",
            str(tx.get("sender", "")),
            str(tx.get("vs", "")),
            _trunc(str(tx.get("message", ""))),
            str(tx.get("bank_id", "")),
            status,
        ]
        for tx, status in zip(transactions, statuses)
    ]
    widths = [
        max(len(headers[i]), max((len(r[i]) for r in rows), default=0))
        for i in range(len(headers))
    ]
    sep = "  "
    print(sep.join(h.ljust(w) for h, w in zip(headers, widths)))
    for row in rows:
        print(sep.join(cell.ljust(w) for cell, w in zip(row, widths)))
 def sort_sheet_by_date(service, spreadsheet_id):
    """Sort the sheet by the Date column (Column B)."""
    # Get the sheet ID (gid) of the first sheet
@@ -104,12 +133,21 @@ def sort_sheet_by_date(service, spreadsheet_id):
    print("Sheet sorted by date.")
-def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None, date_from_str: str = None, date_to_str: str = None, sort_by_date: bool = False):
+def sync_to_sheets(
    spreadsheet_id: str,
    credentials_path: str,
    days: int = None,
    date_from_str: str = None,
    date_to_str: str = None,
    sort_by_date: bool = False,
    dry_run: bool = False,
    print_fio_table: bool = False,
 ):
    print(f"Connecting to Google Sheets using {credentials_path}...")
    service = get_sheets_service(credentials_path)
    sheet = service.spreadsheets()
-    # 1. Fetch existing IDs from Column G (last column in A-G range)
+    # 1. Read existing sync IDs from Column K
    print(f"Reading existing sync IDs from sheet...")
    try:
        result = sheet.values().get(
@@ -120,6 +158,9 @@ def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None,
        # Check and insert labels if missing
        if not values or values[0] != COLUMN_LABELS:
            if dry_run:
                print("Dry run: would write header row")
            else:
                print("Inserting column labels...")
                sheet.values().update(
                    spreadsheetId=spreadsheet_id,
@@ -129,7 +170,7 @@ def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None,
                ).execute()
            existing_ids = set()
        else:
-            # Sync ID is now the last column (index 10)
+            # Sync ID is the last column (index 10)
            existing_ids = {row[10] for row in values[1:] if len(row) > 10}
    except Exception as e:
        print(f"Error reading sheet (maybe empty?): {e}")
@@ -150,8 +191,12 @@ def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None,
    transactions = fetch_transactions(df_str, dt_str)
    print(f"Found {len(transactions)} transactions.")
-    # 3. Filter for new transactions
+    if dry_run:
        print(f"Dry run: window {df_str} to {dt_str}, fetched {len(transactions)} transaction(s) from Fio")
    # 3. Determine NEW/DUP for each transaction
    new_rows = []
    tx_statuses = []
    for tx in transactions:
        sync_id = generate_sync_id(tx)
        if sync_id not in existing_ids:
@@ -169,12 +214,37 @@ def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None,
                tx.get("bank_id", ""),
                sync_id,
            ])
            tx_statuses.append("NEW")
        else:
            tx_statuses.append("DUP")
    # 4. Print table (before early-return so all transactions are shown including DUPs)
    if print_fio_table and transactions:
        _print_fio_table(transactions, tx_statuses)
    if not new_rows:
        if dry_run:
            print("Dry run: would sync 0 new transaction(s).")
        else:
            print("No new transactions to sync.")
        return
-    # 4. Append to sheet
+    # 5. Append to sheet or print dry-run would-write lines
    if dry_run:
        for tx, status in zip(transactions, tx_statuses):
            if status == "NEW":
                print(
                    f"Dry run: would append"
                    f" date={tx.get('date', '')}"
                    f" amount={tx.get('amount', '')}"
                    f" sender={tx.get('sender', '')}"
                    f" vs={tx.get('vs', '')}"
                    f" message={tx.get('message', '')}"
                )
        if sort_by_date:
            print("Dry run: would sort by date")
        print(f"Dry run: would sync {len(new_rows)} new transaction(s).")
    else:
        print(f"Appending {len(new_rows)} new transactions to the sheet...")
        body = {"values": new_rows}
        sheet.values().append(
@@ -184,7 +254,6 @@ def sync_to_sheets(spreadsheet_id: str, credentials_path: str, days: int = None,
            body=body
        ).execute()
        print("Sync completed successfully.")
        if sort_by_date:
            sort_sheet_by_date(service, spreadsheet_id)
@@ -197,6 +266,8 @@ def main():
    parser.add_argument("--from", dest="date_from", help="Start date YYYY-MM-DD")
    parser.add_argument("--to", dest="date_to", help="End date YYYY-MM-DD")
    parser.add_argument("--sort-by-date", action="store_true", help="Sort the sheet by date after sync")
    parser.add_argument("--dry-run", action="store_true", help="Fetch and dedup without writing to the sheet")
    parser.add_argument("--print-fio-table", action="store_true", help="Print aligned table of all fetched transactions with NEW/DUP status (use with --dry-run)")
    args = parser.parse_args()
    try:
@@ -206,7 +277,9 @@ def main():
            days=args.days,
            date_from_str=args.date_from,
            date_to_str=args.date_to,
-            sort_by_date=args.sort_by_date
+            sort_by_date=args.sort_by_date,
            dry_run=args.dry_run,
            print_fio_table=args.print_fio_table,
        )
    except Exception as e:
        print(f"Sync failed: {e}")
--- a/tests/test_reconcile_exceptions.py
+++ b/tests/test_reconcile_exceptions.py
@@ -93,8 +93,8 @@ class TestMultiMonthAllocation(unittest.TestCase):
        self.assertEqual(int(months['2026-02']['paid']), 750)
        self.assertEqual(result['credits'].get('Alice', 0), 500)
-    def test_proportional_underpayment(self):
+    def test_underpayment_fills_earliest_first(self):
-        """Payment < total expected → proportional split; sum of paid == payment amount."""
+        """Payment < total expected → fill earliest months first, spill remainder to later."""
        members = [('Alice', 'A', {'2026-02': (750, 3), '2026-03': (350, 3), '2026-04': (750, 3)})]
        sorted_months = ['2026-02', '2026-03', '2026-04']
        amount = 1250
@@ -103,18 +103,28 @@ class TestMultiMonthAllocation(unittest.TestCase):
        result = reconcile(members, sorted_months, [tx])
        months = result['members']['Alice']['months']
-        paid_02 = months['2026-02']['paid']
+        # 02 filled first (750), then 03 (350), then remainder 150 to 04
-        paid_03 = months['2026-03']['paid']
+        self.assertAlmostEqual(months['2026-02']['paid'], 750, places=2)
-        paid_04 = months['2026-04']['paid']
+        self.assertAlmostEqual(months['2026-03']['paid'], 350, places=2)
        self.assertAlmostEqual(months['2026-04']['paid'], 150, places=2)
        # No CZK lost
        self.assertAlmostEqual(
            months['2026-02']['paid'] + months['2026-03']['paid'] + months['2026-04']['paid'],
            amount, places=2,
        )
-        # All months should be partial (underpaid)
+    def test_fill_first_across_two_transactions(self):
-        self.assertLess(paid_02, 750)
+        """Prior txn fills 02 partially; later txn finishes 02 then spills to 03."""
-        self.assertLess(paid_03, 350)
+        members = [('Matyáš', 'A', {'2026-02': (500, 2), '2026-03': (250, 1)})]
-        self.assertLess(paid_04, 750)
+        sorted_months = ['2026-02', '2026-03']
-        # Sum must equal the original payment (no CZK lost)
+        tx1 = _tx('Matyáš', '2026-02', 200)
-        self.assertAlmostEqual(paid_02 + paid_03 + paid_04, amount, places=2)
+        tx2 = _tx('Matyáš', '2026-02, 2026-03', 550)
-        # 02 and 04 have equal expected → equal allocation
+
-        self.assertAlmostEqual(paid_02, paid_04, places=2)
+        result = reconcile(members, sorted_months, [tx1, tx2])
        months = result['members']['Matyáš']['months']
        self.assertAlmostEqual(months['2026-02']['paid'], 500, places=2)
        self.assertAlmostEqual(months['2026-03']['paid'], 250, places=2)
    def test_single_month_unchanged(self):
        """Single-month payment: full amount goes to that month (regression guard)."""
Author	SHA1	Message	Date
kacerr	10e2e9dc04	Merge pull request 'fix(reconcile): fill earliest month deficit first in multi-month allocations' (#35 ) from fix/fill-first-multi-month-allocation into main All checks were successful Deploy to K8s / deploy (push) Successful in 13s Details Build and Push / build (push) Successful in 6s Details Build and Push / build-go (push) Successful in 52s Details Reviewed-on: #35	2026-05-11 22:01:36 +00:00
Jan Novak	8734089223	fix(reconcile): fill earliest month deficit first in multi-month allocations All checks were successful Deploy to K8s / deploy (push) Successful in 9s Details Replace proportional split with a fill-first loop that allocates min(remaining, deficit) to each matched month in user-supplied order, where deficit = expected - already_paid. Prior transactions' contributions are now properly accounted for, so a second payment on overlapping months fills only what's still owed instead of splitting proportionally by total expected. Surplus after all deficits are covered goes to the credit bucket. Fixes: Matyáš Thér 200+550 showing 566/183 instead of 500/250. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-11 23:59:36 +02:00
Jan Novak	aaa876e593	fix(python): parse Fio 2-digit-year dates + add make sync-debug All checks were successful Deploy to K8s / deploy (push) Successful in 8s Details Build and Push / build (push) Successful in 6s Details Build and Push / build-go (push) Successful in 59s Details Fio's transparent page now serves recent rows as DD.MM.YY while older rows stay DD.MM.YYYY. parse_czech_date only knew the 4-digit form so every recent transfer was silently dropped — make sync-2026 reported zero new transactions. Adds %d.%m.%y and %d/%m/%y to the format list, mirroring the Go-side fix from 2026-05-07. Also adds a Python analog of make go-sync-debug: - --dry-run skips header write / append / sort and prints "would …" lines - --print-fio-table prints aligned per-txn table with NEW/DUP status - make sync-debug [DAYS=N] wrapper (default DAYS=30) - always-on stderr diagnostics in fio_utils: which fetcher was chosen (with FIO_API_TOKEN-unset lag warning) + raw-vs-filtered counts, so this class of "scraper drops everything" bug surfaces immediately. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-11 22:56:49 +02:00
Jan Novak	f25552eef2	chore: CHANGELOG + tick M6.6 (`f6ba85b`) and M6.6.1 (`4276d7b`) in progress tracker All checks were successful Deploy to K8s / deploy (push) Successful in 6s Details Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 14:56:57 +02:00
kacerr	4276d7b915	Merge pull request 'feat(go): M6.6.1 — QR payment popup modal on /adults and /juniors' (#33 ) from feat/go-m6-6-1-payment-qr-modal into main All checks were successful Deploy to K8s / deploy (push) Successful in 9s Details Reviewed-on: #33	2026-05-08 12:54:23 +00:00
kacerr	f6ba85b18f	Merge pull request 'feat(go): M6.6 — /qr, /sync-bank, /flush-cache, /version pages' (#32 ) from feat/go-m6-6-action-pages into main Some checks failed Deploy to K8s / deploy (push) Has been cancelled Details Reviewed-on: #32	2026-05-08 12:54:16 +00:00
Jan Novak	919845518c	feat(go): M6.6.1 — QR payment popup modal on /adults and /juniors All checks were successful Deploy to K8s / deploy (push) Successful in 9s Details Replace bare <a href=/qr> Pay buttons with <button data-*> elements that open an in-page #qrModal (matching Python's showPayQR UX), driven by a new payment-qr.js vanilla-JS IIFE module. Remove the now-dead qrHref / qrHrefAll template helpers from render.go. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 14:49:35 +02:00
Jan Novak	fe935235e8	feat(go): M6.6 — /qr, /sync-bank, /flush-cache, /version pages All checks were successful Deploy to K8s / deploy (push) Successful in 8s Details - GET /qr: Czech QR Platba PNG; ports Python qr_code() exactly (account validation, amount clamping, * stripping, SPD format) - GET /sync-bank: Fio sync → infer → cache flush with captured log - GET+POST /flush-cache: form + action, shows deleted count - GET /version: JSON alias of /api/version (Python parity) - FlushCache() added to membership.Sources; wired through api.Handler - web.ActionHandlers{BankSync} closure-based dep injection for sync - New dep: github.com/skip2/go-qrcode - TestQRBuildSPD (9 cases), TestServeQR, TestServeFlushCache{GET,POST}, TestServeSync, TestServeVersion added Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 14:26:54 +02:00
Jan Novak	e22ab8cc49	chore: CHANGELOG + tick M6.5 in progress tracker — SHA `e53e238` All checks were successful Deploy to K8s / deploy (push) Successful in 7s Details Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 13:19:19 +02:00
kacerr	e53e238ca6	Merge pull request 'feat(go): M6.5 — member-detail modal JS module' (#31 ) from feat/go-m6-5-modal-js into main All checks were successful Deploy to K8s / deploy (push) Successful in 11s Details Reviewed-on: #31	2026-05-08 11:18:46 +00:00
Jan Novak	309c26f209	feat(go): M6.5 — member-detail modal JS module for /adults and /juniors All checks were successful Deploy to K8s / deploy (push) Successful in 8s Details Adds static/js/member-detail.js: fetches /api/<page> once on page load, caches the response, and renders a per-member detail modal on [i] row click. Keyboard nav: Esc closes, ↑/↓ walk visible (filtered) rows. All modal CSS was already in place from M6.1. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 13:14:41 +02:00
Jan Novak	01573faced	chore: CHANGELOG + tick M6.4 in progress tracker — SHA `689f1c0` All checks were successful Deploy to K8s / deploy (push) Successful in 10s Details Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 12:48:42 +02:00
kacerr	689f1c01fd	Merge pull request 'feat(go): M6.4 — Go-native /payments page (grouped-by-person ledger)' (#30 ) from feat/go-m6-4-payments-page into main All checks were successful Deploy to K8s / deploy (push) Successful in 9s Details Reviewed-on: #30	2026-05-08 10:48:04 +00:00
Jan Novak	cb8a09b571	feat(go): M6.4 — Go-native /payments page (grouped-by-person ledger) All checks were successful Deploy to K8s / deploy (push) Successful in 6s Details - Extract AssemblePayments(ctx) from ServePayments in api/handler.go, mirroring the AssembleAdults/AssembleJuniors pattern - Add PaymentsPageData view-model wrapper in render.go - Rewire html_handler.go ServePayments to call AssemblePayments and render with PaymentsPageData - Replace payments.tmpl placeholder with real grouped-by-person ledger: alphabetical member blocks, txn-table (Date/Amount/Purpose/Message), newest-first rows, Unmatched/Unknown bucket - Append ledger CSS classes to app.css (.ledger-container, .member-block, .txn-table, .txn-date/amount/purpose/message, tr:hover) - Add TestPaymentsPage markup test Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 12:29:32 +02:00
Jan Novak	7f87e63b7c	chore: tick M6.3 in progress tracker — SHA `9564103` All checks were successful Deploy to K8s / deploy (push) Successful in 7s Details Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 12:19:13 +02:00
kacerr	95641036cc	Merge pull request 'feat(go): M6.3 — Go-native /juniors page' (#29 ) from feat/go-m6-3-juniors-page into main All checks were successful Deploy to K8s / deploy (push) Successful in 9s Details Reviewed-on: #29	2026-05-08 10:18:40 +00:00
Jan Novak	505d635c66	chore: CHANGELOG entry for M6.3 Go juniors page Some checks failed Deploy to K8s / deploy (push) Failing after 11s Details Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 11:26:08 +02:00
Jan Novak	9f0e4b0ac3	feat(go): M6.3 — juniors page (table, filters, credits/debts, Pay buttons) - Extract AssembleJuniors(ctx) from ServeJuniors JSON handler so HTML and JSON share the same view-model path (mirrors AssembleAdults pattern) - Add JuniorsPageData wrapper in render.go - Wire HTMLHandler.ServeJuniors to AssembleJuniors + render template - Replace 4-line placeholder juniors.tmpl with full template: member table, name filter, month-range filter, totals row, Credits + Debts sections, Pay / Pay All buttons via /qr links (no Unmatched section — matches Python juniors.html parity) - J/A attendance breakdown ("3/500 CZK (4:2J,1A)") and "?" sentinel rendered via MonthCell.Text from buildJuniorMemberRow, no extra template logic needed - All tests pass; make parity reports 3/3 routes OK Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>	2026-05-08 11:25:50 +02:00
kacerr	2cbd98df1a	Merge pull request 'fix: restore Sep+Oct adult merge and stop auto-truncating period selector' (#28 ) from fix/period-selector-restore into main All checks were successful Deploy to K8s / deploy (push) Successful in 7s Details Reviewed-on: #28	2026-05-08 09:13:14 +00:00