Function get_applicable_threshold_seconds 

pub async fn get_applicable_threshold_seconds(
    conn: &mut PgConnection,
    course_id: Uuid,
) -> ModelResult<i32>

Fallback duration threshold (seconds) for a course: the DEFAULT module’s configured threshold, or DEFAULT_CHEATER_THRESHOLD_SECONDS if unset. Only used for legacy flag rows without a recorded triggering module; otherwise the threshold is resolved from that module (see get_suspected_cheater_info_for_user).