Indicate user IDs somehow #1
Description
Currently it's hard to know who's in your chat room except from the list of allowed users, since anyone can use any handle they want and we don't record user IDs anywhere.
It'd be cool to show joins and parts in the UI, but I'm hesitant because A: parts don't get logged due to a node-capnp (?) issue that I can't recall at the moment, and B: if there are lots of periods of inactivity, the channel will fill with join/part noise without any conversation and it'll look bad.
I suppose I could show user IDs on the user pane, but it's hard to imagine how to do that without cluttering it.