Pass AppHandle into run_signal_task so it can emit call-debug events and Tauri events directly. On each RoomUpdate: - emit connect:media:room_update debug event with participant list - emit call-event/participants Tauri event for JS-side diagnostics Helps diagnose whether room join and participant sync is working independently of audio startup. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>