Why all of this? You can just enforce some formatting rules and add a few script to the system mailbox to alter the message (add an issue number, send a notific

Why all of this? You can just enforce some formatting rules and add a few script to the system mailbox to alter the message (add an issue number, send a notification when a change is accepted and merged, etc,...). No need to complicate stuff. Just send a standard plain text email that follows the rules.