Permanently deletes a recording: the audio file is removed everywhere it is kept for playback, and then the recording itself is removed. This cannot be undone — there is no trash and no restore, so keep your own copy of anything you may need again. A recording that a call flow owns or uses is protected and returns 409 until you remove it from the flow. The audio is deleted before the recording, so a failure after that point can leave the recording listed with no audio left to play. Requires an API key with the Admin role.