Wire up playback reporting, fix duration flash, hide video from audio mini player

Playback reporting (position sync / resume-on-another-device):
- player_configure_jellyfin now builds a PlaybackReporter sharing the player
  controller's Arc, so Start/Progress/Stopped actually reach Jellyfin on every
  auth path (login/restore/reauth); previously they never did.
- The PlaybackReporterWrapper now shares the same Arc the controller and MPV
  progress loop report through, instead of a dead parallel Option.
- Android position callbacks now emit throttled progress reports (30s/item),
  mirroring the MPV backend.

Duration flash on pause:
- resolveDuration() prefers the live store duration for the already-loaded
  track over the runTimeTicks estimate, so pausing no longer clobbers the
  slider's max to 0 when runTimeTicks is missing.

Video leaking into audio mini player:
- isVideoItem() also checks the backend PlayerMediaItem mediaType
  discriminator, so a video started via player_play_item (no Jellyfin `type`,
  mediaType "video") no longer surfaces in the audio mini player.

Middle-truncation of long media names:
- New truncateMiddle util applied to track/episode/card/mini-player titles so
  distinguishing tails (episode numbers, suffixes) stay visible.

Adds regression tests for the duration and mini-player fixes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src-tauri/src/lib.rs

@@ -1018,9 +1018,13 @@ pub fn run() {
             let repository_manager_wrapper = RepositoryManagerWrapper(repository_manager);
             app.manage(repository_manager_wrapper);
 
-            // Initialize playback reporter wrapper (initially empty, set on login)
+            // Initialize playback reporter wrapper. This MUST share the same Arc
+            // the player controller and MPV progress loop report through (created
+            // above at `playback_reporter`), otherwise `playback_reporter_init`
+            // would populate a dead, parallel Option and no Start/Progress/Stopped
+            // would ever reach Jellyfin.
             info!("[INIT] Initializing playback reporter wrapper...");
-            let playback_reporter_wrapper = PlaybackReporterWrapper(Arc::new(tokio::sync::Mutex::new(None)));
+            let playback_reporter_wrapper = PlaybackReporterWrapper(playback_reporter.clone());
             app.manage(playback_reporter_wrapper);
 
             info!("[INIT] Application setup completed successfully");