## Summary of the Pull Request
Ensures the Command Palette main window stays hidden from the taskbar
after Windows Explorer restarts. Also updates how app switcher
visibility is managed to prevent unhandled exceptions and avoid startup
crashes when Explorer is not running or is not responsive.
## PR Checklist
- [x] Closes: #40334
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [x] **Tests:** no tests
- [x] **Localization:** nothing to localize
- [x] **Dev docs:** nothing to update
- [x] **New binaries:** no new binaries
- [x] **Documentation updated:** nothing to update
## Detailed Description of the Pull Request / Additional comments
- Settings on the main window are reapplied after the taskbar is
re-created (e.g., after Windows Explorer restarts), restoring visibility
settings for the app switcher and taskbar button.
- Defensive handling of the property AppWindow.IsShownInSwitchers
controlling appearance in system representations such as ALT+TAB and the
taskbar, to avoid errors when Windows Explorer is not running (see
https://github.com/microsoft/microsoft-ui-xaml/issues/8596).
- Prevents application startup failures when the Command Palette is
launched in environments without Windows Explorer.
## Validation Steps Performed
- Verified that the CmdPal main window taskbar button is not visible
after Explorer is restarted (without an attached debugger).
- Verified that CmdPal can be started when Explorer is not running.
- Verified that the CmdPal main window taskbar button is visible after
Explorer is restarted (if a debugger is attached to CmdPal).
