Add Docs For SGLang Native Router

[zhaochenyang20]

Motivation

I added an official document for SGLang native router. Build from https://github.com/sgl-project/sglang/tree/main/rust.

Modifications

Checklist

• Format your code according to the Contributor Guide.
• Add unit tests as outlined in the Contributor Guide.
• Update documentation as needed, including docstrings or example tutorials.

[merrymercy]

address comments?

[zhaochenyang20]

address comments?

Yeah, I am working on this

[ByronHsu]

Thanks!