v0.11.8 — Per-App Cross-Drive Backup (3-2-1 rule)

New feature: backup app data to a secondary storage drive to satisfy
the "different media" requirement of the 3-2-1 backup rule.

- settings.go: CrossDriveBackup struct, AppBackupPrefs.CrossDrive field,
  getter/setter methods, GetOrCreateCrossDrivePassword, preserves
  cross-drive config when toggling nightly backup

- crossdrive.go (new): CrossDriveRunner with rsync and restic backends.
  Validates destination (mount point, writable), prevents source/dest
  overlap, per-app concurrency lock, persists last_run/status/size.

- main.go: wire CrossDriveRunner, register cross-drive-daily (03:30)
  and cross-drive-weekly (04:30 Sundays) scheduler jobs

- router.go: 4 new API endpoints — save config, trigger run, get status,
  run-all. Router now accepts Settings and CrossDriveRunner.

- server.go: Server struct accepts CrossDriveRunner, new web route
  POST /settings/cross-backup/{name}

- handlers.go: deployHandler populates CrossDriveConfig, BackupDestPaths,
  BackupDestWarning, AppBackupEnabled. settingsCrossBackupHandler saves
  config. backupsHandler builds CrossDriveSummary, UnconfiguredApps,
  CrossDriveWarnings for backup page.

- deploy.html: "Biztonsági mentés" card with destination/method/schedule
  dropdowns, last-run status, manual trigger button, flash messages.

- backups.html: "Másolatok másik meghajtóra" section with per-app
  status rows, unconfigured app warnings, "Összes futtatása most" button.

- style.css: margin-bottom fix for .deploy-stale-data, new cross-drive
  card and list styles.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

CONTEXT.md

@@ -7,7 +7,7 @@
 >
 > Ask Claude Code: "Please update CONTEXT.md with what we did today"
 
-Last updated: 2026-02-17 (session 33)
+Last updated: 2026-02-17 (session 35)
 
 ---
 
@@ -20,7 +20,7 @@ Last updated: 2026-02-17 (session 33)
 - Customer deployments use Docker Compose (not Kubernetes) for simplicity
 
 ### felhom-controller (this repo)
-- **Version:** v0.11.6
+- **Version:** v0.11.8
 - **Phase 1:** ✅ COMPLETE — Stack Manager + Deploy Flow
 - **Phase 2:** ✅ COMPLETE — Monitoring & Health (scheduler, CPU/temp, healthchecks.io pings)
 - **Phase 3:** ✅ COMPLETE — Backups (DB dumps, restic integration, manual trigger, **dedicated backup page**)
@@ -36,6 +36,8 @@ Last updated: 2026-02-17 (session 33)
 - **v0.11.3 bugfix:** ✅ COMPLETE — Added `fdisk` package to Dockerfile (provides `sfdisk`; not in `util-linux` on Debian bookworm)
 - **v0.11.4 bugfix:** ✅ COMPLETE — FormatAndMount: fixed sfdisk (wipefs+force+`,,`), mount (explicit device path), mount propagation (rshared), ASCII label, smart partition skip, findmnt verification
 - **v0.11.6:** ✅ COMPLETE — FileBrowser auto-mount sync (`syncFileBrowserMounts()`) + 3 UI fixes (badge color, progress bar, button text)
+- **v0.11.7:** ✅ COMPLETE — Stale data cleanup + FileBrowser sync after migration + deploy page title fix
+- **v0.11.8:** ✅ COMPLETE — Per-App Cross-Drive Backup (3-2-1 rule): rsync/restic to secondary drive, deploy page UI, backup page summary, scheduler jobs, API endpoints
 - **First app deployed:** Paperless-ngx on demo-felhom.eu (2026-02-13)
 - **Running on:** demo-felhom (N100 mini PC) at 192.168.0.162:8080
 - **All Phase 1-5 features working:** deploy, start/stop/restart/update, logs, health-aware states, auth, monitoring, backups, backup detail page, system monitoring page, settings page