`EACCES: permission denied, open 'transcription.json'` when transcription moves to the second audio track (v3 beta 13)

Transcription starts fine but as soon as it moves from the first transcoded track to the second it dies:

ERROR: Encountered error while running task "TRANSCRIBE_CHAPTERS" for book <id>
  err: {
    "message": "EACCES: permission denied, open 'transcription.json'",
    "errno": -13, "code": "EACCES", "syscall": "open", "path": "transcription.json"
  }

The stack points at WhisperCppSTT.ts calling writeFile. Docker, v3.0.0-beta.13.

Resolution: The path is relative - transcription.json with no directory - because leftover debug code wrote the transcript to the process working directory instead of the book's data directory, and that directory isn't writable by the container user. It is a genuine bug, not a misconfiguration on your side: beta.12 and the then-current main branch are unaffected. Upgrade to 3.0.0-beta.14, where it is confirmed fixed. If you're stuck on beta.13, setting PUID/PGID on the container and fixing ownership of the already-created app directories works around it, and keeping those set does no harm after upgrading.