Install PowerShell Core in build workflow

.github/workflows/build.yml

@@ -36,6 +36,17 @@ jobs:
         # Add the BepInEx NuGet feed
         dotnet nuget add source --name bepinex "https://nuget.bepinex.dev/v3/index.json"
     
+    - name: Install PowerShell Core
+      run: |
+        # Update package lists
+        sudo apt-get update
+        # Install PowerShell Core
+        sudo apt-get install -y powershell
+        # Verify installation
+        pwsh --version
+        # Create symlink for compatibility with scripts expecting powershell.exe
+        sudo ln -s /usr/bin/pwsh /usr/local/bin/powershell.exe || true
+    
     - name: Build
       run: dotnet build src/*.csproj --configuration Release -p:CopyToGame=false