Microphone resources released on Scribe setup failure; error crash fixed

Patch Changes

• df7f31a: Scribe realtime now reports microphone setup failures through RealtimeEvents.ERROR instead of leaving an unhandled rejection. Generic local Scribe errors now use the same typed error payload as server errors.
• bb001b1: Release microphone resources when Scribe setup fails after capture starts.
• d8892fd: Guard handleErrorEvent against error messages that arrive without a populated error_event payload. Previously the handler read event.error_event.error_type directly, so a malformed error message threw an unhandled TypeError: Cannot read properties of undefined (reading 'error_type') from inside the message dispatcher. Because the "error" case is not wrapped in a try/catch, the throw escaped onMessage and crashed the consumer instead of surfacing through onError. The payload is now read defensively and always routed to onError.
• 0f12b01: Scribe realtime (microphone mode): release the microphone reliably on teardown.
  • Closing the connection while the async microphone setup is still resolving no longer leaks the MediaStreamTrack/AudioContext; the pipeline is torn down as soon as setup finishes.
  • A microphone frame that arrives after the socket is gone is now dropped instead of throwing WebSocket is not connected.
  • A server-initiated close now releases the microphone too, so consumers reacting to the CLOSE event without calling close() are not left with a live microphone.
  • An app-initiated close() that aborts a still-connecting socket no longer logs a spurious WebSocket closed unexpectedly: 1006 / emits ERROR.