Draft: Add CHIRP implementation

@simon.spannagel alternative to !7 (closed).

While reviewing, I found reviewing changes to both the implementation / formatting and the renaming quite difficult. In this MR, I just added the code and a CI, but did not change any code (except for adjusted paths).

I would propose to leave the MR open and open a separate MR (targeting this branch) that adjusts formatting and clang-tidy related things.