ci: specify C# language for CodeQL analysis

Overrides automatic language detection in CodeQL workflow to analyze only C#. Excludes C/C++ code requiring separate build configurations.

Author: DennisDyallo

.github/workflows/codeql-analysis.yml

@@ -70,6 +70,10 @@ jobs:
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
         uses: github/codeql-action/init@5d5cd550d3e189c569da8f16ea8de2d821c9bf7a  # v3.31.2
+        with:
+          # Override automatic language detection to only analyze C#
+          # C/C++ code in Yubico.NativeShims is built separately (requires CMake/vcpkg)
+          languages: ['csharp']
 
       # Build the project
       - name: Build Yubico.NET.SDK.sln