Phase 06 Tier 1: Complete Backend Implementation - Recovery Tracking & Swap System

COMPLETED TASKS:
✅ 06-01: Workout Swap System
   - Added swapped_from_id to workout_logs
   - Created workout_swaps table for history
   - POST /api/workouts/:id/swap endpoint
   - GET /api/workouts/available endpoint
   - Reversible swaps with audit trail

✅ 06-02: Muscle Group Recovery Tracking
   - Created muscle_group_recovery table
   - Implemented calculateRecoveryScore() function
   - GET /api/recovery/muscle-groups endpoint
   - GET /api/recovery/most-recovered endpoint
   - Auto-tracking on workout log completion

✅ 06-03: Smart Workout Recommendations
   - GET /api/recommendations/smart-workout endpoint
   - 7-day workout analysis algorithm
   - Recovery-based filtering (>30% threshold)
   - Top 3 recommendations with context
   - Context-aware reasoning messages

DATABASE CHANGES:
- Added 4 new tables: muscle_group_recovery, workout_swaps, custom_workouts, custom_workout_exercises
- Extended workout_logs with: swapped_from_id, source_type, custom_workout_id, custom_workout_exercise_id
- Created 7 new indexes for performance

IMPLEMENTATION:
- Recovery service with 4 core functions
- 2 new route handlers (recovery, smartRecommendations)
- Updated workouts router with swap endpoints
- Integrated recovery tracking into POST /api/logs
- Full error handling and logging

TESTING:
- Test file created: /backend/test/phase-06-tests.js
- Ready for E2E and staging validation

STATUS: Ready for frontend integration and production review
Branch: feature/06-phase-06

k8s/backup/README.md

@@ -0,0 +1,51 @@
+# Disaster Recovery & Backup Resources
+
+This directory contains all Kubernetes resources related to disaster recovery and backup operations for Gravl.
+
+## Files
+
+### `postgres-backup-cronjob.yaml`
+Defines automated daily backup CronJob for PostgreSQL database.
+
+**Components:**
+- PostgreSQL Backup ServiceAccount
+- RBAC ClusterRole and ClusterRoleBinding  
+- Daily Backup CronJob (runs at 02:00 UTC)
+- Weekly Backup Test CronJob (runs at 03:00 UTC on Sundays)
+
+**Key Features:**
+- Automated daily full backups of gravl database
+- Gzip compression (level 6)
+- Upload to S3 with encryption (AES256)
+- Backup manifest generation with checksums
+- Automatic retry on failure (up to 3 attempts)
+- 1-hour timeout for backup operations
+
+**Deployment:**
+```bash
+kubectl apply -f postgres-backup-cronjob.yaml
+```
+
+## Manual Backup Scripts
+
+All scripts are in `/workspace/gravl/scripts/`:
+
+- **backup.sh** - Perform manual full database backup to S3
+- **restore.sh** - Restore database from S3 backup
+- **test-restore.sh** - Automated backup restore testing
+- **failover.sh** - Initiate failover to secondary region
+- **failback.sh** - Failback to primary region
+
+## Monitoring & Alerts
+
+- **Prometheus Rules:** ../monitoring/prometheus-rules-dr.yaml
+- **Grafana Dashboard:** ../monitoring/dashboards/gravl-disaster-recovery.json
+
+## Documentation
+
+See `/workspace/gravl/docs/DISASTER_RECOVERY.md` for comprehensive documentation including:
+- RTO/RPO strategy
+- Backup architecture
+- Restore procedures
+- Multi-region failover design
+- Runbooks for disaster scenarios