uwasi instread of browser_wasi_shim

The current Ruby.Wasm is written with separate implementations for Node and Browser.
I can see considerable ingenuity and hard work. Thank you for all the work you have done. Now, I have found a way to solve this difficulty.
The swiftwasm team is developing uwasi, which seems to cover both Node and Browser implementations.
Asciidoctor-wasm implements DefaultRubyVM using this uwasi.

https://github.com/tani/asciidoctor-wasm/blob/f7a240f03c4d33d1235f68cda2497bda874988a0/src/asciidoctor.ts#L1-L21

If this implementation is adopted so that there is no need to separate the Browser and Node implementations, users will not have to distinguish between the Import of the Node and Browser implementations when using Ruby.wasm, which would be a great improvement. Please consider this.

Cheers

比较 Ruby.Wasm 分离的 Node 和 Browser 实现，尤其是 browser_wasi_shim 的使用方式，与链接的 asciidoctor.ts 中使用 uwasi 的 DefaultRubyVM 实现进行比较。完成的标准是实现基于 uwasi 的共享集成，不再要求用户区分 Node 和 Browser 的导入，并在两种环境中验证其行为。