It proved to be too difficult to deal with the flow that clears user
states on stopping the watching of global presence updates. It's not
helped in the least that friends are updated via the API, so there's a
third flow to consider (and the timings therein - both server-spectator
and friends are updated concurrently).
Simplest is to separate the friends flow, though this does mean some
logic and state duplication.
Because I wish to stop seeing "DAILY CHALLENGE WHERE" every day
on #general.
The notifications are constrained to the daily challenge screen only to
not spam users who may not care.
