[Feature Request] Date badge while scrolling #87

A lot of the time when I'm scrolling it isn't immediately apparent what date a conversation is happening on.

Suggestion: Have a a small floating badge at the top that pops up when the user is scrolling that tells the user the day: i.e. "Today", "Yesterday", "Fri, Sep 4"

Similar to the way Signal does it if you want an example. Thanks!