Implement auto host function by macro

[Sieluna]

I find this feature quite useful. If you have time, could you help check if there are any security issues?

• Port simple sample from c
• Make full type integration test

[Sieluna]

🎉

[lum1n0us]

good one

[lum1n0us]

Thank you for your contribution. It would be better to consider and include a wider variety of Rust types.

A string in Rust is different from a C-style string. Given that WAMR is a C-based engine, a Rust string cannot be handled well without transformation.

We might also need to consider ownership for the values of certain types. We should aim to prevent users from worrying about this aspect.

wit-bindgen might provide some insights into type translation. After all, all the types we are dealing with here will first be converted into WebAssembly types, rather than directly into C types.