Add action for building with GCC on Windows

The Windows runners have GCC installed: https://github.com/actions/runner-images/blob/main/images/windows/Windows2022-Readme.md

Create an action that uses GCC to build to make sure that we don't have any gcc-on-windows build issues.

Start with the linked Windows 2022 runner image README to confirm GCC availability, then inspect the repository's CI configuration for the existing build entry point. Done means an action runs the project build with GCC on Windows and exposes any build failures.

Written by the indexing model from the issue text.