Add Deno File System Support

[okikio]

Describe the feature

Deno has a built-in file system storage API's, it would be great if we can use it with unstorage!

Additional information

• [ ] Would you be willing to help implement this feature?

[okikio]

I would love to help implementing this feature but I'm unfortunately unavailable

[so1ve]

I think you can simply import unstorage via npm:unstorage and the file system will be polyfilled

[okikio]

The goal is to support the Deno API is places other than Deno, e.g. there's a Deno library using the Deno FS API, this would allow said library to be supported in the browser or on Node