System Information:

• Distribution: Nobara Linux 43 (64-bit)
• Desktop Environment: KDE Plasma (Wayland session)
• GPU: AMD Radeon 780M (Integrated) + NVIDIA GeForce RTX 4060 Laptop GPU (Discrete)
• Steam Client Version: 1780352834 (from logs)

Issue Description:
When running Steam under a KDE Wayland session with hybrid graphics, clicking the 'X' (close window) button causes the Steam UI to crash rather than cleanly minimizing to the system tray.

The steamwebhelper processes hang indefinitely in the background as zombie processes. Because the application does not cleanly terminate, it leaves behind the steam.pid and steam.pipe lock files in both ~/.steam/ and ~/.local/share/Steam/. Furthermore, the Steam system tray icon fails to register entirely within KDE's System Tray settings, making it impossible to restore the window.

Attempting to relaunch Steam fails silently because it detects the leftover lock files from the crashed session. The only workaround is manually running killall -9 steam steamwebhelper to clear the hanging processes.

Steps to Reproduce:

1. Launch Steam normally on a KDE Wayland session.
2. Click the 'X' button on the window manager title bar to close the main Steam window.
3. Observe that the Steam system tray icon is missing.
4. Attempt to launch Steam again via the application launcher or terminal.

Expected Behavior:
Clicking 'X' should seamlessly minimize Steam to the KDE system tray, allowing the user to restore the window or exit the application cleanly from the tray menu.

Actual Behavior:
The window closes, but the application hangs in the background without a tray icon. Subsequent launches fail until the zombie processes are manually killed or the .pid/.pipe files are deleted.