Reusable format and linting CI action for C++ projects

[eeberhard]

Prompted by @bpapaspyros, we should start to apply formatting and linting checks in the CI for C++ projects, to encourage safer and more efficient co-development and review.

The most ubiquitous resource for C++ is the clang family of tools (clang-format, clang-tidy).

From the marketplace of pre-built actions, I identified https://github.com/cpp-linter/cpp-linter-action as an interesting candidate.

My plan is to make a reusable wrapper action in .github that checks out the .clang-format file from our organization into the workspace and adds some inputs to specify the source path in the repo. In this wrapper we might also consider invoking cmake for compile_commands.json to give clang-tidy the necessary information it needs.

I will test things on a local fork and then make a PR.