Function report_tmc_deletion_rejection 

async fn report_tmc_deletion_rejection(
    conn: &mut PgConnection,
    user_id: Uuid,
    reference: Uuid,
    error: &UtilError,
)

Records a TMC refusal under reference in error_variants/error_occurrences, so support can find it from the reference alone.

Best effort: the deletion has already failed, and failing to record that must not turn a reported outcome into a 500.