Review follow-ups:
- (HIGH) Add real-SQLite round-trip tests for the new query methods so the load-bearing
lexical O-format date ordering is verified, not just mocked: Anomaly
ListByDateRange/CountSince, Snapshot CountSince/ListByEvents grouping, Event Query/GetMany.
- (MED) DetectAnomaliesUseCase: one SaveChanges per event instead of per anomaly.
- (LOW) Route PlacedBetRepository + ExcelExporter date bounds through SqliteDateText.
- (LOW) Backtest: reject a one-sided date range (was silently ignored).
- (LOW) Refresh stale comments after the detector fan-out.
alexei.dolgolyov
b67030ae7f