Function apply_answer 

async fn apply_answer(
    conn: &mut PgConnection,
    row: &CreditRegistration,
    item: Option<&SuotarResponseItem<ImportAttainmentResult>>,
    event: OutcomeEvent<'_>,
) -> Result<bool>

Applies the study registry’s answer for one submitted row. Returns whether the row ended up in a failure state; errors with PreconditionFailed if the row left submitting meanwhile.

Anything the answer disclosed about the attainment is written before the transition, so a row that did move on still keeps the id support needs to find what was created.