CmdPal: change visibility of a search box before bailing out (#46021)

## Summary of the Pull Request

This PR ensures the search box visibility is correctly set by moving the
assignment before the short-circuit bail-out when the window is no
longer visible.

Regressed in 4959273

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## PR Checklist

- [x] Closes: #46019 
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issues) -->
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- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
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for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
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repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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## Detailed Description of the Pull Request / Additional comments

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## Validation Steps Performed

src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml.cs

@@ -586,12 +586,13 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
 
         if (shouldSearchBoxBeVisible || page is not ContentPage)
         {
+            ViewModel.IsSearchBoxVisible = shouldSearchBoxBeVisible;
+
             if (HostWindow?.IsVisibleToUser != true)
             {
                 return;
             }
 
-            ViewModel.IsSearchBoxVisible = shouldSearchBoxBeVisible;
             SearchBox.Focus(FocusState.Programmatic);
             SearchBox.SelectSearch();
         }