Show room name in invitation modal

### Steps to reproduce

1. Be outside the app
2. Receive an invitation to some named room (tested with history readability "members only since they were invited")
3. System notification uses the room name as title (tested with gotify-UP)
4. Click the notification: in-app modal shows room ID, no title

### Outcome

#### What did you expect?
Show room name

#### What happened instead?
- Room name is shown in notification hence clearly available
- Room name is not shown in-app before joining

### Your phone model

Fairphone 4

### Operating system version

LineageOS 20 (Android 13)

### Application version and app store

SchildiChat 1.5.18.sc63-test15 (F-Droid)

### Homeserver

synapse 1.73.0

### Will you send logs?

No

### Are you willing to provide a PR?

No

### Related

#7086