Send host email notifications for reservation alterations accepted on the OTA (not just via Hospitable)

Today, Hospitable sends the "alteration accepted" host email only when the host accepts the alteration in the Hospitable app. If the guest's alteration is accepted directly on the channel (e.g., Airbnb, Vrbo, Booking.com) — whether by the host on the channel's site/app, or auto-accepted under the channel's policy — the reservation updates silently in Hospitable, with no email to the host. For teams that rely on email as their primary operational signal (front desks, ops teams, co-hosts), this means check-in/checkout changes can be missed until a guest arrives on the "wrong" day. The Hospitable Inbox and the channel's own notifications do reflect the change, but email parity is expected. Request: trigger the same (or an equivalent) host email notification for channel-side-accepted alterations, with clear wording that the change originated on the channel.