The sent events of email notifications state the ID of the email
provider the notification was sent through. Together with the flag for
suppressed deliveries it is passed as senders.DeliveryInfo instead of a
positional bool, from the send through the sent commands to the events.
A delivered email states the provider, a suppressed one only the flag.
Events which had no payload before only carry one if either is set.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>