Upload Audio Transmission

POST https://example.com/api/v1/audio/upload

Upload an audio transmission from rtl-airband.

The audio file will be:

1. Saved to local storage
2. Uploaded to S3 (if enabled)
3. Queued for transcription (if enabled)

Supported formats: MP3, WAV, OGG, FLAC

Note: This endpoint is typically called by rtl-airband or a relay service, not directly by end users.