Fix title bar overlapping issue (#43022)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
This pull request introduces a small UI improvement to the
`ShellPage.xaml` file. The change sets a breakpoint for the compact
state of the title bar, which will help the interface adapt better to
different window sizes.

* UI responsiveness: Added `CompactStateBreakpoint="900"` to the
`AppTitleBar` control in `ShellPage.xaml` to improve layout adaptation
for smaller window widths.

**Before:**


https://github.com/user-attachments/assets/5ec424f4-b441-4eff-967f-a97cc92e180a


**After:**


https://github.com/user-attachments/assets/a1487c39-dce7-4055-90e9-aa6ed95e4beb



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## PR Checklist

- [ ] Closes: #xxx
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [x] **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
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
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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---------

Signed-off-by: Shawn Yuan <shuaiyuan@microsoft.com>

src/settings-ui/Settings.UI/SettingsXAML/Views/ShellPage.xaml

@@ -94,6 +94,7 @@
         <controls:TitleBar
             x:Name="AppTitleBar"
             AutoConfigureCustomTitleBar="True"
+            CompactStateBreakpoint="900"
             IsTabStop="False"
             PaneButtonClick="PaneToggleBtn_Click">
             <controls:TitleBar.Resources>