Auto-discover _NT_TARGET_VERSION; remove the TargetVersion axis

- Remove the -TargetVersion parameter and all its plumbing from Build-Samples.ps1 (restoring
  the original hard-coded -p:TargetVersion=Windows10), and drop the TargetVersions column from
  exclusions.csv and Import-SampleExclusions. Only _NT_TARGET_VERSION remains exposed.
- Add Get-NtTargetVersions.ps1, which auto-discovers the valid _NT_TARGET_VERSION values (and
  their NTDDI codes) by parsing the active WDK's DriverGeneral.xml rule. Build-Samples.ps1 uses
  it to validate -NtTargetVersion, default to the latest, and map to the msbuild code, so a new
  WDK version needs no script change (accepts '10.0.<build>' or the short '<build>' tag).
- CI: ci.yml and ci-pr.yml gain a 'discover' job that emits the newest-N versions as JSON; the
  build matrix consumes it via fromJSON, so there is no hand-maintained version list anywhere.
  Build-ChangedSamples.ps1 treats Get-NtTargetVersions.ps1 as a full-build trigger.
- Docs updated accordingly.

Co-authored-by: Copilot <[email protected]>

2 files changed, 52 insertions, 14 deletions

diff --git a/.github/workflows/ci-pr.yml b/.github/workflows/ci-pr.yml
index 7983c8dd..8119c94c 100644
--- a/.github/workflows/ci-pr.yml
+++ b/.github/workflows/ci-pr.yml
@@ -8,20 +8,39 @@ on:
       - '**.md'
       - 'LICENSE'
 jobs:
+  # Auto-discover the available _NT_TARGET_VERSION values from the active WDK so the build
+  # matrix never needs a hand-maintained version list. Change -Newest to build more/fewer.
+  discover:
+    name: discover _NT_TARGET_VERSIONs
+    runs-on: windows-2025-vs2026
+    outputs:
+      versions: ${{ steps.nt.outputs.versions }}
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+
+      - name: Install Nuget Packages
+        run: nuget restore .\packages.config -PackagesDirectory .\packages\
+
+      - name: Discover the newest _NT_TARGET_VERSION values
+        id: nt
+        shell: pwsh
+        run: |
+          $json = .\Get-NtTargetVersions.ps1 -Newest 4 -AsMatrixJson
+          "versions=$json" | Out-File -FilePath $env:GITHUB_OUTPUT -Append -Encoding utf8
+          Write-Host "Discovered _NT_TARGET_VERSION matrix: $json"
+
   build:
     name: build ${{ matrix.nt.tag }} ${{ matrix.configuration }} ${{ matrix.platform }}
+    needs: discover
     strategy:
       fail-fast: false
       matrix:
         configuration: [Debug, Release]
         platform: [x64, arm64]
-        # _NT_TARGET_VERSION = the WDK library version drivers link against (newest first).
-        # Each { version, tag } runs as its own parallel job; trim this list to reduce CI load.
-        nt:
-          - { version: '10.0.28000', tag: '28000' }
-          - { version: '10.0.26100', tag: '26100' }
-          - { version: '10.0.22621', tag: '22621' }
-          - { version: '10.0.22000', tag: '22000' }
+        # _NT_TARGET_VERSION values are auto-discovered by the 'discover' job from the active
+        # WDK, so there is no version list to maintain here.
+        nt: ${{ fromJSON(needs.discover.outputs.versions) }}
     runs-on: windows-2025-vs2026
     steps:
       - name: Check out repository code
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 022ae4f6..de856d55 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,20 +11,39 @@ on:
     # Runs every Saturday at 00:00 PST (08:00 UTC)
     - cron: '0 8 * * 6'
 jobs:
+  # Auto-discover the available _NT_TARGET_VERSION values from the active WDK so the build
+  # matrix never needs a hand-maintained version list. Change -Newest to build more/fewer.
+  discover:
+    name: discover _NT_TARGET_VERSIONs
+    runs-on: windows-2025-vs2026
+    outputs:
+      versions: ${{ steps.nt.outputs.versions }}
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+
+      - name: Install Nuget Packages
+        run: nuget restore .\packages.config -PackagesDirectory .\packages\
+
+      - name: Discover the newest _NT_TARGET_VERSION values
+        id: nt
+        shell: pwsh
+        run: |
+          $json = .\Get-NtTargetVersions.ps1 -Newest 4 -AsMatrixJson
+          "versions=$json" | Out-File -FilePath $env:GITHUB_OUTPUT -Append -Encoding utf8
+          Write-Host "Discovered _NT_TARGET_VERSION matrix: $json"
+
   build:
     name: build ${{ matrix.nt.tag }} ${{ matrix.configuration }} ${{ matrix.platform }}
+    needs: discover
     strategy:
       fail-fast: false
       matrix:
         configuration: [Debug, Release]
         platform: [x64, arm64]
-        # _NT_TARGET_VERSION = the WDK library version drivers link against (newest first).
-        # Each { version, tag } runs as its own parallel job; trim this list to reduce CI load.
-        nt:
-          - { version: '10.0.28000', tag: '28000' }
-          - { version: '10.0.26100', tag: '26100' }
-          - { version: '10.0.22621', tag: '22621' }
-          - { version: '10.0.22000', tag: '22000' }
+        # _NT_TARGET_VERSION values are auto-discovered by the 'discover' job from the active
+        # WDK, so there is no version list to maintain here.
+        nt: ${{ fromJSON(needs.discover.outputs.versions) }}
     runs-on: windows-2025-vs2026
     steps:
       - name: Check out repository code