Include Demo3 app in release artifacts

Add MaterialDesign3.Demo.Wpf (Demo3App) alongside the existing MainDemo.Wpf
(DemoApp) in the build and release workflows:
- Upload Demo3App build output as a separate artifact in build_artifacts.yml
- Download, zip, and attach Demo3App.zip to the GitHub release in release.yml

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Keboo

.github/workflows/build_artifacts.yml

@@ -72,3 +72,9 @@ jobs:
         with:
             name: DemoApp
             path: "src/MainDemo.Wpf/bin/${{ env.buildConfiguration }}"
+
+            - name: Upload Demo3 App
+              uses: actions/upload-artifact@v4
+              with:
+                  name: Demo3App
+                  path: "src/MaterialDesign3.Demo.Wpf/bin/${{ env.buildConfiguration }}"

.github/workflows/release.yml

@@ -135,18 +135,27 @@ jobs:
           name: DemoApp
           path: demo-app
 
+      - name: Download Demo3 App Artifacts
+        uses: actions/download-artifact@v8
+        with:
+          name: Demo3App
+          path: demo3-app
+
       - name: Zip Demo App
         run: zip -r DemoApp.zip demo-app/*
 
+      - name: Zip Demo3 App
+        run: zip -r Demo3App.zip demo3-app/*
+
       - name: Download Release Notes
         uses: actions/download-artifact@v8
         with:
           name: ReleaseNotes
 
       - name: Create Release
         run: |
-          # We can't use glob pattern because of this bug https://github.com/cli/cli/issues/5099
-          gh release create v${{ inputs.milestone }} --repo '${{ github.repository }}' --draft --latest --title "${{ inputs.milestone }}" --notes-file ReleaseNotes.md (Get-Item '${{ github.workspace }}/nugets/*.nupkg') '${{ github.workspace }}/DemoApp.zip'
+            # We can't use glob pattern because of this bug https://github.com/cli/cli/issues/5099
+            gh release create v${{ inputs.milestone }} --repo '${{ github.repository }}' --draft --latest --title "${{ inputs.milestone }}" --notes-file ReleaseNotes.md (Get-Item '${{ github.workspace }}/nugets/*.nupkg') '${{ github.workspace }}/DemoApp.zip' '${{ github.workspace }}/Demo3App.zip'
 
   update_wiki:
     needs: [create_release]