Restructure step 4: local library and media identity

- L1 (core, offline): release names with kinds (episode, movie, extra:
  OP/ED/Opening/Ending/NC/PV/OVA…), folder hints (season and name from
  parentheticals, ranges), one show across folders, gaps and next with
  skipped numbers, junk ignored, stable keys.
- L2 (app, device-owned cache): AniList match with synonyms and
  sequel walking, episode mapping across cours (AnimeFlow runs when
  signed in), art and episode titles, "Wrong show?" pins per show or
  folder, episode offsets; lazy, spaced requests, works offline.
- Files tab as a library: poster cards, show pages with banner, gap
  prompt, extras, movies, Wrong show? and Episode numbers.
- media.ref produced for local files, Jellyfin (provider ids) and links,
  carried in swaps and Up next; receivers name media from it.
- Hosting relays each Jellyfin item through its own server's login.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/desktop/lib/src/queue/queue_ui.dart

@@ -9,7 +9,6 @@ import 'package:sync_relay_core/core.dart';
 
 import '../controls/controls_probe.dart' show ControlsHold;
 import '../controls/minimal/style.dart';
-import '../files/scanner.dart' show FileKind, kindOf;
 import '../jellyfin/images.dart';
 import '../jellyfin/session_media.dart' show EpisodeLink;
 import '../screens/home/picked_media.dart';