Fixes two playback failures reported in #21 and #23:
- Idle speakers retain their inactive status when reconnecting after token refresh, preventing them from taking playback away from the selected speaker. Deactivation also handles protobuf messages that omit the default-false boolean.
- Playback explicitly requests the next queue item when a track is unavailable, preserving the server's queue version instead of waiting for an unsolicited response.
Validation includes local regressions that fail against the earlier implementations, 697 passing tests and Ruff, and live Qobuz/Sonos checks. The live test confirmed that Living Room reconnects as inactive while Kitchen keeps playing, and that the reported album advances automatically from track 4 to 6, and recovers from the second unavailable track after manual advancement.
Mypy retains 70 known errors in 13 files; this release does not resolve that existing typing debt.