Refactor: extract audio.py, add 50 unit tests
- Extract MPRISController and PulseController into src/turnup/audio.py;
turnupd.py imports from there, dropping ~270 lines of duplicated code
- Add [project.optional-dependencies] dev = [pytest] and pytest testpaths
to pyproject.toml
- Add tests/test_audio.py: 31 tests covering MPRISController player
matching, volume clamping, cache TTL, and PulseController MPRIS-first
routing, PA fallback, and drain_events
- Add tests/test_protocol.py: 19 tests covering parse_messages framing,
multi-message buffers, garbage skipping, and knob conversion helpers
- All 50 tests pass (pytest 9.0, Python 3.14)
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