DetectAnomaliesUseCase was issuing one ISnapshotRepository.ListByEventAsync
call per event each cycle, with each call rehydrating that event's bets via
Include(s => s.Bets) — O(N) SQLite round-trips and N Include payloads on
every detection cycle.
* Add ISnapshotRepository.ListByEventsAsync(IReadOnlyCollection<EventId>, …)
returning a per-event dictionary; events with no snapshots in range get
Array.Empty<OddsSnapshot>() so the caller doesn't need a presence check.
* Implementation uses a single .Where(s => ids.Contains(s.EventCode))
query and groups in memory.
* DetectAnomaliesUseCase loads the whole batch once before the foreach,
then ProcessEventAsync receives the per-event slice as a parameter.
* Tests updated to stub the new method; per-event-failure test now
exercises an AddAsync throw rather than a snapshot-load throw, since
individual snapshot loads no longer fail per-event.
alexei.dolgolyov
66ae038243