This commit makes reactions in the status timeline work.
There are two things prior to this commit that are broken:
1. The logic that opens the reaction context menu always expects
and instance of `chatsView` because it tries to calculate a users
nickname. Such an instance isn't always available in that context, so
the nickname logic has been moved to `appMain` for now, removing that
dependency and therefore making it work in both, the chat view as well
as the status view.
2. While 1) makes the context menu work, it turns out that adding and
removing reactions inside the status timeline is still not working.
The reason for that is, that the reactions component maintains its own
`messageList`, which isn't aware of the fact that reactions for messages
coming from chats of `ChatType.Profile`, need to go into a dedicated
message list for `ChatType.Timeline`.
In other words, reactions are sent and removed from message in messagelists
that don't actually exist.
This commit fixes both of these things by ensuring the message lists
maintained by reactions are timeline aware. Also ensuring updates are
done correctly.
