docs: document automated backup configuration

Updated documentation to reflect complete backup setup:

**CLAUDE.md Updates:**
- Added detailed repository configuration (hidrive-backup)
- Documented all 11 backup plans with schedules and retention
- Explained volume mounting strategy with prefixed names
- Added configuration management instructions
- Included maintenance schedule (weekly prune/check)

**README.md Updates:**
- Added "Backup Operations" section with CLI commands
- Documented automated backup schedule (2-8 AM daily)
- Added backup protocol to security section
- Updated mission status with backup system indicator
- Included next backup time and repository status

**compose.yaml Updates:**
- Restored backrest_config volume (needed for proper operation)
- Removed direct config.json mount (causes write conflicts)
- Config copied into volume after container start

All 11 backup plans now documented:
- postgres, redis, directus (uploads/bundle)
- awesome, gotify, scrapy, n8n
- filestash, linkwarden, letsencrypt

Retention policies range from 3-12 months with yearly backups
for critical data (postgres, directus, letsencrypt).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

restic/compose.yaml

@@ -7,12 +7,10 @@ services:
     volumes:
       # Backrest application data
       - backrest_data:/data
+      - backrest_config:/config
       - backrest_cache:/cache
       - backrest_tmp:/tmp
 
-      # Configuration file (mount directly to override)
-      - ./config.json:/config/config.json:rw
-
       # Backup destination
       - ${RESTIC_BACKUP_PATH:-/mnt/hidrive/users/valknar/Backup}:/repos
 
@@ -59,6 +57,8 @@ services:
 volumes:
   backrest_data:
     name: ${RESTIC_COMPOSE_PROJECT_NAME}_data
+  backrest_config:
+    name: ${RESTIC_COMPOSE_PROJECT_NAME}_config
   backrest_cache:
     name: ${RESTIC_COMPOSE_PROJECT_NAME}_cache
   backrest_tmp: