Restart audio worker on stream start after reconnect

[balloob-travel]

Summary

• restart the audio worker when a new player stream starts after a reconnect
• keep reconnect cleanup scoped to connection state so daemon hardware volume monitoring stays active
• add a regression test covering stream start after connection reset

Testing

• uv run pytest tests/test_audio_connector.py tests/test_decoder.py
• uv run ruff check sendspin/audio_connector.py sendspin/daemon/daemon.py sendspin/tui/app.py tests/test_audio_connector.py
• uv run mypy sendspin