Both dovecot-quota-threshold triggers and the daily expiry routine
will now expunge oldest messages from mailboxes automatically
when the mailbox reaches 75% of max_mailbox_size.
Delta Chat users should not see any warnings (at 80/95 percent) or bounce messages,
and existing over-quota mailboxes should start receiving mails again.
Similar data is already generated by fsreport
available for the relay operator
and metrics for prometheus are generated by mtail.
Closes <https://github.com/chatmail/relay/issues/431>
This change adds XDELTAPUSH capability.
Delta Chat clients detecting this capability
can set /private/devicetoken IMAP metadata
on the inbox to subscribe for Apple (APNS)
notifications.
Notifications are implemented in a new
`chatmail-metadata` service
which handles requests to set /private/devicetoken
IMAP metadata from Delta Chat clients
and /private/messagenew requests from
push_notification_lua script.
To avoid sending notifications for
MDNs, webxdc updates and Delta Chat sync messages,
messages with Auto-Submitted header are ignored
by setting $Auto keyword (flag) on them in Sieve script
and skipping such messages in push_notification_lua script.
Outgoing messages are also ignored.
