[Linux] Couldn't exit the program when receive the shutdown request form GUI

[SweetLoverFT]

Describe the bug

On debian11-based YinheKylin system, the avalonia program will block in the background even if user click shutdown the machine from GUI

To Reproduce

1. Prepare a machine (e.g., x86 chipset) that install the system from YinheKylin iso file:
   a. Go to the official site: https://www.kylinos.cn/support/trial/download/
   b. Choose Desktop version V10 sp1, (e.g, x86 chipset if the machine is x86 chipset)
   c. Download the iso and burn the image to USB: https://iso.kylinos.cn/web_pungi/download/cdn/kz4Ju6NbSg7DUA9mlf5M2rqZeBRat1vC/Kylin-Server-V11-2503-Release-General-20250715-X86_64.iso
2. Just write a simple Avalonia app, with ShutdownMode.OnExplicitShutdown
3. Run the application
4. Click shutdown from start menu

The issue reproduce:

1. The YinheKylin system will promote "Please close the background application" with a list
2. The app couldn't be close

Expected behavior

Avalonia should handle the "Inhibit" signal, and perform a normal exit procedure, so that the system could poweroff correctly

Avalonia version

e.g. 11.3.11

OS

Linux

Additional context

1. Currently happened on Debian11-based YinheKylin system
2. Of cause, poweroff won't be blocked, this is a correct behavior