When migrating from Temporal to Catalyst, how should I handle duplicate external side effects from workflow replays?

When migrating, review your existing idempotency patterns—like idempotency keys or transactional outboxes—as Catalyst uses the same at-least-once model. Catalyst's agent runners don't change replay behavior. Ensure your activities are idempotent or implement reconciliation logic. Catalyst's verifiable execution can help audit side-effect outcomes, but does not prevent duplicates.