v1.106.0 — The mail you can trust

You can now see every email your shop sent, whether it arrived, and what to do about the ones that did not.

Sent mail on the client — every email to a customer now sits on their profile alongside their bookings and payments. One that did not arrive says so.
A failures list in Settings — what failed, grouped by cause, each with the next thing to do. A waiver link that died on a missing date of birth links straight to the diver.
A dead address stops being written to — an address that hard-bounces is suppressed. A temporary bounce, like a full mailbox, is not, because that person is still reachable tomorrow.
Receipts and confirmations always try — they are never silently suppressed. If one cannot be delivered you see it in the list rather than never hearing about it.