fix: Align NestJS entity columns with service expectations

Resolved 12 TypeScript compilation errors caused by mismatched column names between TypeORM entities and service layer.

Entity changes:
- NotificationsConfig: Renamed email_alerts_enabled → email_enabled, added email_address, standardized notification event column names (notify_on_start, notify_on_stop, notify_on_crash, etc.)
- ScheduledTask: Renamed is_active → is_enabled, added last_run timestamp
- TeamMember: Renamed accepted_at → joined_at to match service expectations
- Role: Added description column for custom role metadata

Service changes:
- JwtStrategy: Updated to reference joined_at instead of accepted_at

All services now compile cleanly against updated entity schemas.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -4,6 +4,17 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+### Fixed (NestJS Entity Alignment — 2026-02-15)
+
+**Backend (NestJS):**
+- `NotificationsConfig` entity — Renamed `email_alerts_enabled` → `email_enabled`, added `email_address` column
+- `NotificationsConfig` entity — Renamed notification columns to match service expectations: `notify_on_start`, `notify_on_stop`, `notify_on_crash`, `notify_on_wipe_start`, `notify_on_wipe_complete`, `notify_on_wipe_failure`, `notify_on_player_threshold`, `player_threshold`
+- `ScheduledTask` entity — Renamed `is_active` → `is_enabled`, added `last_run` column
+- `TeamMember` entity — Renamed `accepted_at` → `joined_at` to match service expectations
+- `Role` entity — Added `description` column
+- `JwtStrategy` — Updated to reference `joined_at` instead of `accepted_at`
+- Resolved all 12 TypeScript compilation errors caused by entity/service column mismatches
+
 ### Added (Frontend Gap Closure — 2026-02-15)
 
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