Arvamer

If I understand XDG Base Directory specification correctly, `$XDG_DATA_DIRS` is used to find application specific data like images or sound effects. If you don't want to add more functions, `{get_,}app_{dir,root}(SharedData)`...

Actually there is function in `std::env` that returns path to executable (`current_exe`), there is no need to use `fs::read_link("/proc/self/exe")`.