f622dadf95
Adds a background forward-test engine that records flat-stake "paper" bets for directional anomalies as they fire and settles them when results arrive, measuring the detector's live, out-of-sample edge — the antidote to backtest overfitting. The results UI is a follow-up. - Domain: PaperBet entity (Rate>1 / Stake>0 invariants, Open factory, SettleAgainst — Won pays stake x rate, else Lost) + AnomalyEvidenceSide.RateFor. - Application: OpenPaperBetsUseCase (directional + score gate, dedups by AnomalyId, picks the post-flip favourite and its locked-in rate) and SettlePaperBetsUseCase (Won when pick == winner else Lost; ungraded events stay open; batched result lookup). - Infrastructure: PaperBetEntity + config (TEXT decimals, unique AnomalyId index, Outcome index), repository, mapping, additive AddPaperBets migration, and PaperTradingWorker (config-gated, baseline since-marker, open+settle per cycle). - Config: PaperTradingOptions / appsettings PaperTrading (Enabled:false default). - 25 tests: domain settlement, both use cases, and a real-SQLite round-trip incl. the unique-AnomalyId double-open backstop.