Delivery notification sent on state transition to delivered

Delivery confirmation from the carrier is a natural trigger for re-engagement — a 'your order arrived' email is the highest-open-rate message in ecommerce. Without it, the customer only knows their order arrived because they were home when it showed up. The platform misses the opportunity to prompt a review, confirm customer satisfaction, or detect a non-delivery claim early. This is an iso-25010:2011 reliability issue: the system receives or computes a delivery event and fails to act on it. The delivery email also serves as the customer's receipt of physical delivery, which matters if they later dispute receiving the item.

Add a delivery email trigger in the handler or job that transitions orders to 'delivered' — typically src/jobs/delivery-check.ts for carrier-webhook polling or a webhook handler for real-time updates.

// In your delivery handler or job:
await transitionOrder(orderId, 'delivered', 'system', 'Carrier confirmed delivery')

await sendDeliveryConfirmationEmail({
  to: order.user.email,
  orderNumber: order.id,
  deliveredAt: new Date(),
  reviewUrl: `https://yoursite.com/orders/${order.id}/review`,
})

Add sendDeliveryConfirmationEmail to lib/email/order-emails.ts alongside the other order email functions.