Richard
b21da1c2c7
Fingerprint-snapshot foundation + strategy-drift calculator (#3/#5 groundwork) TraderAnalytics is one row per trader, overwritten every recalculation, so there is no history to detect strategy drift (#3) or edge fade (#5) against. Add the missing time series: - TraderFingerprintSnapshot entity (score, category concentration, conviction, P50/P90 sizing, hold duration, trades/week, category-mix JSON, trait-set JSON) + migration AddFingerprintSnapshots (indexed by TraderId, CapturedAt). - FingerprintSnapshotService (Infrastructure): CaptureDueAsync snapshots every copy-relevant trader (CopytradingScore >= 40) at most ~once/day; wired into ScoringAndAlertsWorker. GetDriftAsync reads latest-vs-baseline drift. - FingerprintDriftCalculator (pure, Application): flags score drop, concentration shift, sizing jump, conviction sign-flip, category-mix TVD, trait-set change. - GET /api/traders/{id}/fingerprint-drift?baselineDays=14 read endpoint. - Tests: drift calculator (4 scenarios) + capture service (copy-relevance, throttle, drift read). This is the shared foundation both #3 (drift alarm) and #5 (edge freshness) build on. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> @