///|
/// Package entry point for moonrockz/directories.
/// Public API: BaseDirs, UserDirs, ProjectDirs; path join(), path_sep() (see path_util.mbt, platform).
/// OS detection: platform(), is_windows(), Platform enum (see platform.mbt).
/// Paths and home/config/cache/data are OS-specific (Windows LOCALAPPDATA/APPDATA, Unix XDG/HOME).