Function update_audio 

pub(crate) async fn update_audio(
    pool: &PgPool,
    id: i64,
    update: &AudioUpdate<'_>,
) -> Result<(), Error>

Updates a stream with the encoded MP3 audio, end timestamp, and frame count.

Called by Tier 3 after the voice stream ends and MP3 encoding completes. The AudioUpdate struct groups the audio blob, timing, and optional slow-data fields decoded from the voice frames.

Errors

Returns sqlx::Error on query failure.