[UI tests] Add accessibility IDs to FancyZones to fix part UI tests (#41316)

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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
Not sure why some text changed — for example, this button was ‘Launch
layout editor’, but in the UI it now shows as ‘Open layout editor’, so
it can’t be found :
<img width="1159" height="87" alt="image"
src="https://github.com/user-attachments/assets/d407a8fc-2876-4a85-9637-14d5923493d2"
/>

But using accessibility IDs is always more reliable.



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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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## Validation Steps Performed

src/modules/fancyzones/FancyZonesEditor.UITests/Utils/FancyZonesEditorHelper.cs

@@ -41,9 +41,13 @@ namespace Microsoft.FancyZonesEditor.UnitTests.Utils
             public const string MainWindow = "MainWindow1";
             public const string Monitors = "Monitors";
             public const string NewLayoutButton = "NewLayoutButton";
+            public const string LaunchLayoutEditorButton = "LaunchLayoutEditorButton";
 
             // layout card
             public const string EditLayoutButton = "EditLayoutButton";
+            public const string GridCustomLayoutCard = "GridcustomlayoutCard";
+            public const string Grid9LayoutCard = "Grid-9Card";
+            public const string CanvasCustomLayoutCard = "CanvascustomlayoutCard";
 
             // edit layout window: common for template and custom layouts
             public const string DialogTitle = "EditLayoutDialogTitle";