[Bug] GNOME 46: gnome-session-properties window unresponsive due to MetaWindowActorX11 allocation failure

**Describe the bug**
When opening "Startup Applications" (gnome-session-properties) with Tiling Shell enabled, the window becomes completely unresponsive (cannot be clicked, moved, resized, or closed). The GNOME Shell journal shows repeated critical errors indicating that the Mutter compositor fails to allocate geometry for the X11 window actors.
Disabling Tiling Shell immediately resolves the issue, confirming it is caused by an interaction between this extension and GTK3/X11 system dialogs on GNOME 46.

**To Reproduce**
Steps to reproduce the behavior:
1.Ensure Tiling Shell extension is enabled.
2.Check journalctl -f /usr/bin/gnome-shell for allocation errors.
3.Open "Startup Applications Preferences" (gnome-session-properties).
4.Observe that the window appears but does not respond to any input.

**Screenshots**
If applicable, add screenshots to help explain your problem.

**Information (please complete the following):**
- Tiling Shell version: v17.3 (build 76)
- GNOME version: 46.0
- Ubuntu version: 24.04

**Additional context**
Logs:
```
Aug 06 09:18:26 pc gnome-shell[11657]: [tilingshell] [GlobalState] added workspace 2
Aug 06 09:18:26 pc gnome-shell[11657]: [tilingshell] [LayoutWidget] relayout not needed
Aug 06 09:18:26 pc gnome-shell[11657]: [tilingshell] [LayoutWidget] relayout not needed
Aug 06 09:18:26 pc gnome-shell[11657]: 0xc00003c: Frame has assigned frame counter but no frame drawn time
Aug 06 09:18:26 pc gnome-shell[11657]: 0xc00003c: Frame has assigned frame counter but no frame drawn time
Aug 06 09:18:26 pc gnome-shell[11657]: 0xc00003c: Frame has assigned frame counter but no frame drawn time
Aug 06 09:18:27 pc gnome-shell[11657]: [tilingshell] [LayoutWidget] relayout not needed
Aug 06 09:18:27 pc gnome-shell[11657]: [tilingshell] [LayoutWidget] relayout not needed
Aug 06 09:18:27 pc gnome-shell[11657]: [tilingshell] [GlobalState] deleted workspace
Aug 06 09:18:27 pc gnome-shell[11657]: [tilingshell] [TilingManager 0] deleted workspace
Aug 06 09:18:27 pc gnome-shell[11657]: [tilingshell] [TilingManager 1] deleted workspace
```

Reproduce the issue with Tiling Shell enabled by opening gnome-session-properties on GNOME 46, while monitoring journalctl -f /usr/bin/gnome-shell. Then trace the extension's window-management behavior around the reported MetaWindowActorX11 allocation failure. Done means the dialog remains clickable, movable, resizable, and closable without repeated compositor errors.

Written by the indexing model from the issue text.