Function would_change_credit_registration_via_suotar 

pub async fn would_change_credit_registration_via_suotar(
    conn: &mut PgConnection,
    course_id: Uuid,
    updates: &ModuleUpdates,
) -> ModelResult<bool>

Whether applying updates to course_id would flip enable_credit_registration_via_suotar on any module.

Only support may put a module on the live study registry path, but the module editor round-trips the flag on every save, so gate on an actual change rather than on the field being sent. A module the update creates, and one not in the course, count as currently off; update_modules rejects the latter.