Crash/hang since message permalinks introduced

### Steps to reproduce

There seem to be a few ways to cause the app to hang. At first I was able to reasonably reliably cause the crash by clearing the app cache, then restarting and very quickly following reply permalinks in a room. Another way I've just found to cause the same hang is to very quickly open and close the same room (quicker than the animations play).
It feels to me like it's a deadlock/race when jumping to a permalink and paginating? The pagination spinner always seems to be present on the frozen screen when the app crashes.

### Outcome

#### What did you expect?
No crashy

#### What happened instead?
The app visually stops. All animations and transitions freeze and it becomes unresponsive until Android offers to kill it. Even force-closing it doesn't help- you still have to either wait for Android or force-kill it from the App page in settings.

### Your phone model

Pixel 8 Pro

### Operating system version

Android 14

### Application version and app store

740571b + a few tweaks

### Homeserver

Synapse develop

### Will you send logs?

No

### Are you willing to provide a PR?

No