Fix asterix conflict with talk

[nickvergessen]

Reverse of nextcloud/spreed#5831

Simplifying the logic a bit

Steps

1. Open Talk
2. Before the room list finished loading open another tab
3. Check that Talk marks the tab with * already, otherwise write a message in a channel where this user is a member of
4. Trigger a notification: occ notification:generate

Before

* * …

After

* …

[PVince81]

👍

[PVince81]

with time passing, I find more and more that it would be convenient to only have a single channel for all possible notifications, updates, messages,

[nickvergessen]

I was also thinking about a lib which apps just tell it should yield the asterix, use a new base page title, etc and the lib itself unmarks the asterix when the page is opened again. So no one has to worry about anything.