Initial DSC v3 support for PowerToys (#41132)

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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

Tasks checklist
- [X] Implement DSC infra in PowerToys
- [X] Implement Settings DSC resource
  - [X] Implement Get, Set, Test, Export, Schema
  - [X] Generate manifest (DSC resource JSON)
- [X] Added Unit Tests
- [x] Add `NJsonSchema` v11.4.0 to the stream
- [x] Package the manifest files so dsc.exe can discover them
- [x] Add `PowerToys.DSC.exe` to the PATH (maybe?)
- [x] Add `InstallLocation` in the registry key so `winget configue
export` can export the PowerToys DSC resources
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## PR Checklist

- [X] Closes: #37276
- [X] **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
- [X] **Localization:** All end-user-facing strings can be localized
- [x] **Dev docs:** Added/updated
- [x] **New binaries:** Added on the required places
- [x] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [x] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [x] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [x] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [x] **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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or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

---------

Co-authored-by: vanzue <vanzue@outlook.com>
Co-authored-by: Kai Tao (from Dev Box) <kaitao@microsoft.com>
Co-authored-by: Leilei Zhang <leilzh@microsoft.com>

.pipelines/v2/templates/job-build-project.yml

@@ -271,6 +271,23 @@ jobs:
       env:
         SYSTEM_ACCESSTOKEN: $(System.AccessToken)
 
+  # Build PowerToys.DSC.exe for ARM64 (x64 uses existing binary from previous build)
+  - task: VSBuild@1
+    displayName: Build PowerToys.DSC.exe (x64 for generating manifests)
+    condition: ne(variables['BuildPlatform'], 'x64')
+    inputs:
+      solution: src/dsc/v3/PowerToys.DSC/PowerToys.DSC.csproj
+      msbuildArgs: /t:Build /m /restore
+      platform: x64
+      configuration: $(BuildConfiguration)
+      msbuildArchitecture: x64
+      maximumCpuCount: true
+
+  # Generate DSC manifests using PowerToys.DSC.exe
+  - pwsh: |-
+      & '.pipelines/generateDscManifests.ps1' -BuildPlatform '$(BuildPlatform)' -BuildConfiguration '$(BuildConfiguration)' -RepoRoot '$(Build.SourcesDirectory)'
+    displayName: Generate DSC manifests
+
   - task: CopyFiles@2
     displayName: Stage SDK/build
     inputs: