Fix speaker-track readiness race: skip mixed-file wait when tracks exist

tests/test_recording.py

@@ -92,3 +92,25 @@ def test_meeting_sink_ignores_silence_only_and_unknown_users(tmp_path):
     assert manifest["tracks"] == []
     # Mixed archive still finalized and valid.
     assert _read_wav_frames(mixed) == SILENCE * 2
+
+
+def test_meeting_sink_ignores_writes_after_cleanup(tmp_path):
+    """Verify that writes after cleanup() are silently dropped."""
+    mixed = tmp_path / "meeting.wav"
+    tracks_dir = tmp_path / "tracks"
+    sink = recording.MeetingSink(str(mixed), str(tracks_dir))
+
+    alice = FakeUser(111, display_name="Alice")
+    sink.write(alice, FakeData(SPEECH))
+    sink.cleanup()
+
+    # These writes should be dropped, not cause crashes or corrupt the files.
+    sink.write(alice, FakeData(SPEECH))
+    sink.write(None, FakeData(SILENCE))
+
+    # Mixed file should contain only the pre-cleanup frame.
+    assert _read_wav_frames(mixed) == SPEECH
+    assert _read_wav_frames(tracks_dir / "track-111.wav") == SPEECH
+    # Manifest should still reference Alice.
+    manifest = json.loads((tracks_dir / "tracks.json").read_text())
+    assert len(manifest["tracks"]) == 1