[BlueBubbles] Support for Sending/Recieving Multipart Messages

[joshuafhiggins]

When sending an image and a text in the same message, the bridge takes the incoming event and uses the text as the subject field in iMessage and sends the message with the attachment. BlueBubbles Server supports sending multipart messages which may be able to fix this issue. This feature would also be helpful in making sure that, when multiple attachments are sent at the same time, they are all sent at once, instead of spamming one by one or failing to send when expiring after 60 seconds. Although Beeper Mini supports image stacks which would show this change, I'm unsure if the new Beeper Android app or any other client currently supports this feature. I do remember hearing somewhere that Beeper intends on adding support but I may be misremembering or making that up

[trek-boldly-go]

More power to you if you can figure out how to make that endpoint work with Bluebubbles. I can't recall what the issue was when we tried to implement it that way before, but when we asked the BB devs about it they basically said they don't even use the multiparty message endpoint in their own UI. We sort of figured no one would even be able to tell a difference, and just used the subject for the text.