feat: initial dashboard implementation and robust attendance parsing

- Added a Makefile to easily run project scripts (fees, match, web, image)
- Modified attendance.py to dynamically handle a variable number of header rows from the Google Sheet
- Updated both attendance calculations and calculate_fees terminal output to show actual attendance counts (e.g., '750 CZK (3)')
- Created a Flask web dashboard (app.py and templates/fees.html) to view member fees in an attractive, condensed, terminal-like UI
- Bound the Flask server to port 5000 and added a routing alias from '/' to '/fees'
- Configured Python virtual environment (.venv) creation directly into the Makefile to resolve global pip install errors on macOS

Co-authored-by: Antigravity <antigravity@deepmind.com>

docs/fee-calculation-spec.md

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+# Fee Calculation Spec — Tuesday Practices
+
+## Data Source
+
+- Google Sheet: `1E2e_gT_K5AwSRCDLDTa2UetZTkHmBOcz0kFbBUNUNBA`
+- Sheet: first sheet only (Tuesday practices, 20:30–22:00)
+- Public export URL (CSV): `https://docs.google.com/spreadsheets/d/1E2e_gT_K5AwSRCDLDTa2UetZTkHmBOcz0kFbBUNUNBA/export?format=csv`
+
+## Sheet Structure
+
+| Row | Content |
+| --- | --- |
+| 1 | Header: title in col A, dates in cols D+ (format `M/D/YYYY`) |
+| 2 | Venue per date (irrelevant for pricing) |
+| 3 | Total attendees per date |
+| 4+ | Member rows: Name (col A), Tier (col B), Total (col C), attendance TRUE/FALSE (cols D+) |
+
+Member rows end when the Name column is empty.
+
+## Tiers
+
+| Code | Meaning | Pays from this sheet? |
+| --- | --- | --- |
+| A | Adult | Yes |
+| J | Junior | No (paid via separate attendance sheet) |
+| X | Exempt | No |
+
+## Fee Rules (Adults only)
+
+Fees are calculated per calendar month based on the number of attended practices in that month.
+
+| Practices in month | Fee |
+| --- | --- |
+| 0 | 0 CZK |
+| 1 | 200 CZK |
+| 2 or more | 750 CZK |
+
+## Payment Matching
+
+### Bank Account
+
+- Fio banka transparent account: `2800359168/2010`
+- Owner: Nathan Heilmann
+- Public view: `https://ib.fio.cz/ib/transparent?a=2800359168`
+
+### Data Access
+
+- **Without API token**: scrape the public transparent account HTML page
+- **With API token**: Fio REST API at `https://fioapi.fio.cz/v1/rest/periods/{token}/{from}/{to}/transactions.json`
+  - Token is generated in Fio internetbanking (Settings → API)
+  - Rate limit: 1 request per 30 seconds per token
+  - Available fields: date, amount, currency, sender account, sender name, VS, SS, KS, user identification, message, type, and more
+
+### Matching Approach
+
+Payments are matched to members using best-effort heuristics, with uncertain matches flagged for manual review.
+
+1. **Name matching**: Normalize (strip diacritics, lowercase) sender name and message text, compare against member names and nicknames
+2. **Month parsing**: Extract Czech month names (leden, únor, ...) and numeric patterns (01/26, 1/2026) from the message
+3. **Amount validation**: Check if amount aligns with expected fees (200, 750, or multiples)
+4. **Multi-person splitting**: When a message references multiple members, split the payment across them
+
+### Advance Payments
+
+If a payment references a month with no attendance data yet, it is tracked as **credit** on the member's account. The credit is applied once that month's attendance is recorded.
+
+## PII Constraint
+
+No member names or personal data are committed to git. All data is fetched at runtime from the Google Sheet and bank account.