feature request: support for WASI preview 2 component model

[HarikrishnanBalagopal]

The example code doesn't compile with wat2wasm

https://github.com/WebAssembly/component-model/blob/main/design/mvp/Explainer.md#component-definitions

(component
  (component
    (core module (func (export "one") (result i32) (i32.const 1)))
    (core module (func (export "two") (result f32) (f32.const 2)))
  )
  (core module (func (export "three") (result i64) (i64.const 3)))
  (component
    (component
      (core module (func (export "four") (result f64) (f64.const 4)))
    )
  )
  (component)
)

$ wat2wasm --version
1.0.34
$ wat2wasm main.wat 
main.wat:1:2: error: unexpected token "component", expected a module field or a module.
(component
 ^^^^^^^^^
main.wat:2:3: error: unexpected token (, expected EOF.
  (component
  ^

Other tools that support the component model https://component-model.bytecodealliance.org/language-support.html#building-a-component-with-wasm-tools

[sbc100]

IIUC the component model is defined here: https://github.com/WebAssembly/component-model. And its completely separate/independent from WASI (WASI just happens to depend on it right?)