- StackDataProvider interface extended with StopStack/StartStack
- backup.Manager.GetStackHDDMounts() delegates to stackProvider
- RestoreApp() auto-stops app before restic restore, restarts after (even on failure)
- stackAdapter in main.go wires StopStack/StartStack through to stacks.Manager
- GET /api/backup/snapshots?stack={name} filters snapshots by app HDD paths via filterSnapshotsByPaths()
- Restore section simplified: no path list, per-app filtered snapshots, human-friendly timestamp format, single calm warning, empty-result inline message
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>