* test: add unit tests for common utilities from PR #1249
* incorporate review comments specific to tests formatting
* use filesystem API instead of std::system for safer cleanup
* Add ghc/filesystem submodule v1.5.14 for portable C++17 filesystem support
* fix: add cmake/GhcFilesystem.cmake for CI submodule auto-checkout
* incorporate review comment
* incorporate review comment
habajpai-amd