"Select Colour Scheme" doesn't prefill either option after installation.

[RokeJulianLockhart]

Describe the bug

"Select Colour Scheme" doesn't prefill either option after installation.

To Reproduce

Steps to reproduce the behavior:

1. Install https://f-droid.org/repo/com.manichord.mgit_240.apk
2. Enter Settings.
3. Invoke the dialog to choose a colour scheme – "Select Colour Scheme".

Expected behavior

One of the options – the current option – should be prefilled.

Screenshots

Smartphone (please complete the following information):

• Device: Fairphone FP5
• OS: Android 14
• App Version: 1.7.0 from https://f-droid.org/repo/com.manichord.mgit_240.apk

Additional context

Ideally, it should automatically adhere to the system theme. However, that's the purview of another FR.