driver1998

Results 12 issues of driver1998

This, together with #366, fixes building on LLVM/Clang based MinGW environments, like CLANG* environments in MSYS2, including Windows on ARM (CLANGARM64).

The `std::basic_fstream` implementation in libc++ does not allow constructing with a derived class of `std::filesystem::path` like `agi::fs::path`. (There is a `is_same_v` constraint.) Workaround by getting its underly string manually. Fixes...