Feature request: VKontakte-like chats between Smithereen users only

[koke228666]

Also, some switch between all activitypub messages and smithereen only (like in VKontakte, between mail and IM) would be good

[grishka]

I thought about that way back when I was building the current messages feature but came to the conclusion that having two types of messages where different one works for different use cases would be way too confusing for the average user.

[c-cesar]

ActivityPub allowing multiple chats with the same actor is a real challenge to this kind of interface, but I miss being able to see the messages as a conversation. Today, a conversation is split between an inbox and an outbox, and this is confusing. I think using the modern e-mail paradigm, showing a list of conversations and opening them in a threaded or sequential view will work better.