This is needed (for now) in order to parallelize ingame_chat, because
one of the handled messages updates this value on the server. It turns
out that the value is not actually used on the server, only the client,
so this was mostly a matter of threading this back to the correct place.
Additionally, we took the opportunity to modify the UI to not log you
into the game until your character was confirmed to be loaded, which
was a todo item that lets us simplify some error handling logic and
remove stuff from global state.
