onResendEmailDeliveryDelayed emits email.delivery_delayed when a delivery is
temporarily deferred rather than permanently bounced.
automations/monitor-resend-delay.automation.ts
account defaults to the project binding. Returns
{ type: "email.delivery_delayed"; createdAt; data }. Resend can continue retrying
after this event, so wait for delivered, bounced, or failed events for a final
outcome.