R1:e4b7263bf8dc

Conpherence - Differentiate audience of Threads/Rooms with icon

Summary:
Fixes T7629 plus an un filed bug that's breaking creating new threads since we need to add participants EVEN EARLIER than we were doing it now that policy is actually enforced.

Back to the main thrust of this, there is one UI corner case - in the main view if you go from 1:1 to 1:1:1 (i.e. add a 3rd recipient, or Nth in a row) the icon only updates on page reload. I figure this will get sorted out at a later refactor as we make the…