* feat(admin): implement visual theme cards, album search, and system status diagnostics
* fix(admin): resolve type-checking build errors in SettingsEditor and status route
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Co-authored-by: ralksta <ralksta@users.noreply.github.com>
- Add /api/video/[id] route with Range header support for seeking
- Add /api/webhook route for Immich event-driven cache invalidation
- Add streamVideo() to ImmichClient with 206 Partial Content support
- Support album description overrides in gallery.yaml
- Add videoUrl() helper to lib/urls.ts
- Export cache.delete() and cache.clear() methods