Support recursive copy of files

Right now axoasset only supports copying one asset at a time, it would be nice if it supported a recursive option where we could just pass a `origin_folder` and a `dist_folder` and it would copy the files and create the folders

example code used in `fs_extra`: https://docs.rs/fs_extra/latest/src/fs_extra/lib.rs.html#190-223

related https://github.com/axodotdev/oranda/pull/82

Start by inspecting axoasset's existing single-asset copy API, then compare its behavior with the linked fs_extra example. Implement the recursive origin_folder-to-dist_folder behavior, including creating destination folders; done means the requested directory tree and files are copied successfully.

Written by the indexing model from the issue text.