'Nextcloud Talk Federation was updated...' after remote capabilities update

[Antreesy]

Joining a federated conversation for the first time after logging in shows the Nextcloud Talk Federation was updated, please reload the page message. From the code it makes sense, as the capabilities would not be found in the browser storage so the hash can not match, but from a user point of view looks like a bug. I think that I read somewhere that this was a known issue, but I mention it just in case.

Originally posted by @danxuliu in https://github.com/nextcloud/spreed/pull/12879#pullrequestreview-2214494808

[Antreesy]

We can try to make them reactive, and on update:

• make a comparison local <-> remote or old_remote <-> new_remote
• if there are only changes that can be safel updated, we don't show the toast message<
• otherwise keep it (same as with local server changes, have to reload)

[SystemKeeper]

Also the toast seems to never disappear? Even after switching conversations.