- Remove TURN decks (3/4), clean up MIDI, layout
- Single cart player with 3-item autoload queue + continue toggle
- Event logging (SessionLogger), mic tracking, large mic timer widget
- LUFS metering moved from external ports to internal master mix
- Master output WAV recording with top-bar REC toggle
- Music mix output (ch 3-8 only, no mics)
- Preview bar for playlist auditioning
- Merged show log with [SONG][CART][TALK] prefixes
- Live CSV writer for OBS song display (~/live_songs.csv)
- Misc fixes: preview race condition, datetime import for recording
