audio playback fixes

tests/audio-dispose.test.ts

@@ -3,7 +3,7 @@
  *
  * The `q` (quit) action routes through `process.exit(0)`, which bypasses
  * Solid's onCleanup (where useAudio's onCleanup disposes the backend). To
- * keep spawned players (mpv/ffplay/afplay) from surviving the host, useAudio
+ * keep spawned players (mpv) from surviving the host, useAudio
  * registers a `process.on("exit")` handler that synchronously disposes the
  * backend. The exit handler's whole job is "kill the child process", so this
  * test pins the contract directly: a backend holding a real spawned subprocess
@@ -11,7 +11,7 @@
  *
  * Uses a real `Bun.spawn(["sleep", "60"])` subprocess as a stand-in for the
  * player process, injected into the (private) `proc` slot of an MpvBackend —
- * mpv/ffplay/afplay all share the identical kill-on-dispose pattern, so
+ * mpv is the only real backend, and it uses the kill-on-dispose
  * exercising one is enough to guard the family.
  */
 import { test, expect } from "bun:test";