fix: include juniors in payment-inference roster

infer_payments was building member_names from get_members_with_fees()
(adults sheet only). Junior-only members were invisible to the matcher,
so a payment message containing an exact junior name would produce a
fuzzy review match against a different adult sharing the same first name.

Fix: union the adult and junior rosters (deduped via canonical_member_key)
so all members are candidates. The existing exact-name short-circuit in
match_members then handles precedence correctly.

Two regression tests added for the Jáchym Kubík / Jáchym Hrušák case.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

scripts/infer_payments.py

@@ -11,8 +11,8 @@ sys.path.append(os.path.dirname(os.path.abspath(__file__)))
 
 from googleapiclient.discovery import build
 from sync_fio_to_sheets import get_sheets_service, DEFAULT_SPREADSHEET_ID
-from match_payments import infer_transaction_details
-from attendance import get_members_with_fees
+from match_payments import infer_transaction_details, canonical_member_key
+from attendance import get_members_with_fees, get_junior_members_with_fees
 
 def parse_czk_amount(val) -> float:
     """Parse Czech currency string or handle raw numeric value."""
@@ -96,10 +96,19 @@ def infer_payments(spreadsheet_id: str, credentials_path: str, dry_run: bool = F
         print(f"Current header: {header}")
         return
 
-    # 2. Fetch members for matching
+    # 2. Fetch members for matching — union adults + juniors so junior-only
+    # members (e.g. kids not on the adult sheet) are visible to the matcher.
     print("Fetching member list for matching...")
-    members_data, _ = get_members_with_fees()
-    member_names = [m[0] for m in members_data]
+    adult_members, _ = get_members_with_fees()
+    junior_members, _ = get_junior_members_with_fees()
+
+    seen: set[str] = set()
+    member_names: list[str] = []
+    for m in adult_members + junior_members:
+        key = canonical_member_key(m[0])
+        if key not in seen:
+            seen.add(key)
+            member_names.append(m[0])
 
     # 3. Process rows
     print("Inferring details for empty rows...")