fix(ci): move NUGET_API_KEY check from job-level if to workflow steps

.github/workflows/native-multi-platform.yml

@@ -29,11 +29,11 @@ jobs:
             build_config: Release
             library_path: build/libannoy_c.so
             release_asset_name: libannoy_c-linux-x64.so
-          - id: macos-x64
-            runs_on: macos-13
-            build_config: Release
-            library_path: build/libannoy_c.dylib
-            release_asset_name: libannoy_c-macos-x64.dylib
+          # - id: macos-x64
+          #   runs_on: macos-15-intel
+          #   build_config: Release
+          #   library_path: build/libannoy_c.dylib
+          #   release_asset_name: libannoy_c-macos-x64.dylib
 
     steps:
       - name: Checkout repo
@@ -141,8 +141,8 @@ jobs:
             -OutputPath "dist/annoy.net.unitypackage" `
             -PackageRoot "dev.trainhead.annoy.net" `
             -WindowsLibrary "release-assets/windows-x64/annoy_c-windows-x64.dll" `
-            -LinuxLibrary "release-assets/linux-x64/libannoy_c-linux-x64.so" `
-            -MacLibrary "release-assets/macos-x64/libannoy_c-macos-x64.dylib"
+            -LinuxLibrary "release-assets/linux-x64/libannoy_c-linux-x64.so"
+            # -MacLibrary "release-assets/macos-x64/libannoy_c-macos-x64.dylib"
 
       - name: Upload unitypackage artifact
         uses: actions/upload-artifact@v4
@@ -189,16 +189,19 @@ jobs:
             -OutputDirectory "dist/nuget" `
             -PackageVersion "${{ env.ANNOY_PACKAGE_VERSION }}" `
             -WindowsLibrary "release-assets/windows-x64/annoy_c-windows-x64.dll" `
-            -LinuxLibrary "release-assets/linux-x64/libannoy_c-linux-x64.so" `
-            -MacLibrary "release-assets/macos-x64/libannoy_c-macos-x64.dylib"
+            -LinuxLibrary "release-assets/linux-x64/libannoy_c-linux-x64.so"
+            # -MacLibrary "release-assets/macos-x64/libannoy_c-macos-x64.dylib"
 
       - name: Run NuGet smoke tests
         shell: pwsh
         run: |
           $restorePackagesPath = "$pwd/.nuget-packages"
+          $localPackageSource = "$pwd/dist/nuget"
+          $publicPackageSource = "https://api.nuget.org/v3/index.json"
 
           dotnet restore tests/Annoy.NuGetSmoke/Annoy.NuGetSmoke.csproj `
-            --source "$pwd/dist/nuget" `
+            --source $localPackageSource `
+            --source $publicPackageSource `
             -p:AnnoyPackageVersion="${{ env.ANNOY_PACKAGE_VERSION }}" `
             -p:RestorePackagesPath=$restorePackagesPath
 
@@ -237,37 +240,48 @@ jobs:
         with:
           generate_release_notes: true
           fail_on_unmatched_files: true
+          # macOS artifacts are temporarily disabled in CI.
           files: |
             release-assets/**/*.dll
             release-assets/**/*.so
-            release-assets/**/*.dylib
             release-assets/**/*.unitypackage
             release-assets/**/*.nupkg
 
   publish-nuget:
     name: Publish NuGet package
     needs: package-nuget
-    if: startsWith(github.ref, 'refs/tags/') && secrets.NUGET_API_KEY != ''
+    if: startsWith(github.ref, 'refs/tags/')
     runs-on: ubuntu-24.04
+    env:
+      NUGET_API_KEY: ${{ secrets.NUGET_API_KEY }}
 
     steps:
+      - name: Skip publish when NuGet key is not configured
+        if: env.NUGET_API_KEY == ''
+        shell: pwsh
+        run: |
+          Write-Host "NUGET_API_KEY is not set. Skipping NuGet publish."
+
       - name: Setup .NET
+        if: env.NUGET_API_KEY != ''
         uses: actions/setup-dotnet@v4
         with:
           dotnet-version: 8.0.x
 
       - name: Download NuGet artifact
+        if: env.NUGET_API_KEY != ''
         uses: actions/download-artifact@v4
         with:
           name: nuget-package
           path: nuget-artifacts
 
       - name: Publish package to NuGet.org
+        if: env.NUGET_API_KEY != ''
         shell: pwsh
         run: |
           Get-ChildItem "nuget-artifacts/*.nupkg" | ForEach-Object {
             dotnet nuget push $_.FullName `
-              --api-key "${{ secrets.NUGET_API_KEY }}" `
+              --api-key "$env:NUGET_API_KEY" `
               --source "https://api.nuget.org/v3/index.json" `
               --skip-duplicate
           }