Replace the JSON-based import/export with a proper backup system that copies
the SQLite database file directly. Supports manual on-demand backups, periodic
scheduled backups via node-cron, configurable retention, file download, and
full database restore.
- Add backupService with VACUUM INTO for safe DB copies
- Add backupScheduler following healthcheckScheduler pattern
- Add 6 admin API endpoints (create, list, download, restore, delete, schedule)
- Add BackupPanel UI with backup table, confirmation dialogs, schedule config
- Add backup fields to SystemSettings schema
- Remove old ImportExportPanel, exportService, importService, and related code
- JSON import/export with conflict resolution (skip/overwrite) + admin UI
- Ping history sparklines on AppWidget and AppCard (24h, 288 points)
- Hourly cleanup job for old AppStatus records
- User theme preferences (hue, saturation, mode, background, locale)
- Settings page with ThemeCustomizer (sliders, toggles, live preview)
- Prisma migration for user preference fields
- i18n translations for all new strings (EN/RU)
Add admin layout with auth guard, user management (CRUD + group membership),
group management, system settings (auth mode, registration, theme, healthcheck),
permission editor component, and global search API endpoint.
alexei.dolgolyov