Ringing timeout way too short

### Steps to reproduce

1. Press the button for a call in a 1:1 room
2. Ringing starts on the caller's end
3. Ringing stops after 30 seconds.

In many situations, due to various network delays, phone wakeups / power saving etc this is way too short and the receiving phone never even starts ringing before the call is forcibly cut off.

### Outcome

#### What did you expect?
For the call to keep ringing, at the very minimum for a minute if not two or more, as used to be the case

#### What happened instead?
Call ringing cuts off after 30 seconds

I know this did not used to be the default behaviour, it used to ring almost indefinitely which is very important in some situations.

I have looked through all issues mentioning "ring" or "call" but none seem relevant.
As far as I understand this behaviour is meant to be controlled by [this timeout](https://github.com/element-hq/element-x-android/blob/c5bb18c0a705a5db235a43f02300b5368cd104ed/appconfig/src/main/kotlin/io/element/android/appconfig/ElementCallConfig.kt#L15) which is set to 90 seconds (unless this refers to the receiving end), but it's stopping at 30s.

### Your phone model

Pixel 8a

### Operating system version

Android 16

### Application version and app store

Element X 25.12.0 from Play Store

### Homeserver

matrix.org

### Will you send logs?

No

### Are you willing to provide a PR?

Yes

Start with appconfig/src/main/kotlin/io/element/android/appconfig/ElementCallConfig.kt at the linked timeout, then trace which side of the 1:1 call enforces the observed 30-second cutoff. Reproduce the call flow and confirm that ringing remains active for the intended longer interval before considering the issue done.

Written by the indexing model from the issue text.