Build an example that calling golang std fs or `io/fs` package from opendal

[Xuanwo]

Hello, everyone. I'm from opendal community, a unified data access layer that enables users to seamlessly and efficiently retrieve data from various storage services.

I recently discovered rust2go and am considering the possibility of calling the Golang standard fs or io/fs package from opendal. This would allow Rust users to directly utilize Golang's fs interface.

There isn't a real use case so far, but OpenDAL itself is a medium-sized project and serves as a great demonstration of how rust2go works. It's easy to work with, and I believe it will be a good example.