Fixes backing track display to show when the player popup is open,
matching JamTrack behavior. Also properly clears all state when closed.
Changes:
- Added showBackingTrackPlayer boolean from backingTrackData
- Updated conditional render to check showBackingTrackPlayer
- Track now displays only when popup is actually open
- handleBackingTrackMainClose now clears backingTrackData
- Also closes the modal to ensure popup is hidden
Display flow:
1. User selects backing track
2. handleBackingTrackSelected opens file and sets backingTrackData
3. Player popup opens (showBackingTrackPlayer = true)
4. WebSocket MIXER_CHANGES updates mixerHelper.backingTracks
5. Track appears in session screen (both conditions met)
6. Clicking close removes track and closes popup
Close flow:
1. Calls closeMedia() to close native client media
2. Clears backingTrackData (hides track and popup)
3. Closes modal (ensures popup window closes)
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
e4d51fb452