Game startup hangs at BAR splash screen

### Description

Some attempts to launch the game hang at the BAR intro screen. The screen looks like this:

Music is playing and I can see the BAR mouse cursor. Clicking with mouse and pressing keyboard buttons doesn't help.
This happens about every second or third start.
Closing the game with ALT-F4 , deleting the cache folder in `~/.local/state/Beyond All Reason/cache` and then starting the game works as a reliable workaround.

### Expected Behaviour

On starting the game it starts with a visible main menu.

### Actual Behaviour

Upon starting the game it stops making progress and is stuck at the "BAR" intro screen without showing the main menu.

### Reproduction steps

**edit start**:

- Start the game
- Launch s skirmish until the game begins (commander bot on map)
- close the game, **then...**:

**edit end**

Start the game on **arch linux** (at least on my machine).
Installed through the AUR package:

Name : beyondallreason-appimage
Version : 1.2988.0-3
https://aur.archlinux.org/packages/beyondallreason-appimage

### Other

Logs of a failed start (Aborted with ALT-F4):

[20260101191949_infolog.txt](https://github.com/user-attachments/files/24402656/20260101191949_infolog.txt)

Start by reviewing the attached infolog from the failed start and reproducing the hang on Arch Linux with the AUR package. Compare launches with and without deleting ~/.local/state/Beyond All Reason/cache; done means repeated starts reach the visible main menu without requiring ALT-F4 or cache removal.

Written by the indexing model from the issue text.