Adds the Audio.* namespace and its platform backend, the audio subsystem #22 was
blocked on.
- runtime/native/audio.ll: the macOS backend, AVAudioPlayer driven through the
objc runtime C ABI (no ObjC/C source), same style as cocoa.ll — snd_load /
play / stop / playing / set_volume / set_rate. Spliced and linked with
AVFoundation only when a windowed build actually uses Audio.* (needed_framework,
since AVAudioPlayer is reached by name).
- runtime/native/audio.ludic: the Audio.* runtime — a handle table, master
volume/pitch, a single music channel. load/play/play_sound/play_music/stop/
stop_music/stop_all/volume/pitch/is_playing. Every native call is
is_windowed()-guarded, so a headless build carries the API as no-ops (load
returns 0, is_playing false) and needs no audio device.
- compiler: Audio.* namespace dispatch, g_uses_audio splice, snd_* intrinsics +
declarations, and the conditional AVFoundation link in both the canonical
(main.ludic) and dev-runner (x app) paths.
- docs: a full docs/language/audio section (10 method pages); check-impl green.
- test: examples/library/audio.ludic self-asserts the headless no-op path.
Playback is out-of-band and never feeds the deterministic sim, but triggers are
frame-driven so replays fire the same sounds. Reseeded; suites green (80 + 29).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>