Function media_revoke 

pub async fn media_revoke(
    token: String,
    server: State<'_, MediaServerHandle>,
    channel: AppHandle,
) -> Result<(), AppError>

Immediately revoke a single media token.

After revocation, any in-flight request using the token will receive a 403 response on the next check (or 404 after GC). The media:revoked event is emitted so the frontend can react (e.g. show an expired-token message).

Errors

This command is idempotent — revoking an already-revoked or unknown token is not an error.