Copy operational notifications (Phase 2b)

Per-owner feed των safety-relevant copy events — destination tripping rejection breaker, account-protection ή prop-rule breach, panic flatten. On by default (App:Copy:NotificationsEnabled, default true); set false για να σιγήσει. Δικό concept στο Copy context, ξεχωριστό από market/AI AlertRule aggregate.

Πώς λειτουργεί

Ίδιο out-of-band host→sink→drainer pattern όπως execution-transparency log:

CopyEngineHost ──Notify(record)──▶ ICopyNotificationSink
                                     │
             (notifications off) NullCopyNotificationSink   → discards (no-op; unchanged engine)
             (notifications on)  ChannelCopyNotificationSink → bounded DropOldest channel
                                     │
                                     ▼
                            CopyNotificationDrainer (BackgroundService)
                                     │  resolves each profile's owner, batches
                                     ▼
                            CopyNotification feed  ◀── GET /api/copy/notifications

• Host Notify(...) non-blocking, never throws — never touches DB, never delays copy.
• Drainer resolves owning UserId από κάθε notification's profile; notification του οποίου το profile gone (owner unresolvable) dropped, όχι orphaned.
• CopyNotification = append-only, per-row-acknowledgeable feed (όχι aggregate).

Τι ανυψώνεται

Kind	Severity	When
DestinationTripped	Warning	G8 rejection budget εξαντλήθηκε; νέα opens paused για το cooldown.
AccountProtectionTriggered	Critical	ZuluGuard equity floor/ceiling breached; opens latched (SellOut liquidates).
PropRuleBreached	Critical	Prop daily-loss / trailing-drawdown breached; destination flattened + locked out για την ημέρα.
FlattenAll	Critical	Panic flatten executed; κάθε destination κλειστή + locked.
TokenInvalidated	(reserved)	Το destination's token δεν ισχύει πλέον; awaiting rotation.

API

• GET /api/copy/notifications (owner-scoped) — οι πρόσφατες notifications του user (πιο πρόσφατα 200) διαφορά όλα profiles, plus unacknowledged count.
• POST /api/copy/notifications/{id}/acknowledge — mark one read.

Configuration (App:Copy)

Setting	Default	Effect
NotificationsEnabled	true	Emit safety notifications + τρέξε το drainer. false → no-op sink.

Tests

• Unit (CopyNotificationTests) — tripped destination raises DestinationTripped; panic flatten raises profile-level FlattenAll. Via capturing sink.
• Integration (CopyNotificationDrainerTests, real Postgres) — drainer resolves owner + persists; notification για unknown profile dropped.
• DST — host emits fire-and-forget με no-op default sink, ώστε το copy stress suite παραμένει green (23/23).