L2 Input Cleanup

Current state: - L2 participates in the quit-combo timing path. - Standalone L2 also reaches the quick-favorite TODO/log path.

Expected v1: - Preserve the intentional L1+R1+L2 quit combo. - Make standalone L2 perform quick favorite only where supported. - Avoid noisy debug logs for normal L2 use.

Queue Rebuild Cleanup

Current state: - Queue list items are rebuilt inline in render and input paths.

Expected v1: - Add one helper to build current queue view items. - Use it from draw, input, and art refresh code.

Playing Index Race

Current state: - finish_loading() briefly sets playing_track_index = 1 before scanning for the actual index.

Expected v1: - Resolve the desired index first, then assign once. - Avoid transient mismatch in UI/current-track state.