Feat: Allow stylex.create nested within TS namespaces

[nonzzz]

What changed / motivation ?

Now current work is WIP, but i need to clarify some situations.

Linked PR/Issues

#829

Additional Context

Q: Should we add a manipulateOptions for babel plugin to infer the coming file is typescript or others?
Q: Should the export expression check of Theme's API be cancelled? If embedded in typescript namespace.

Pre-flight checklist

• I have read the contributing guidelines
  Contribution Guidelines
• Performed a self-review of my code

[necolas]

Why can't the TS source code be converted to JS before babel/stylex runs?

[nmn]

Could you make one quick change to the tests and then I can merge

[nmn]

Yup. This should fix the issue for now!

[nmn]

Can we update the existing transform function to use typescript based on opts.filename instead?

That way, we won't need two mostly duplicate functions.

[nonzzz]

BTW, I think that's not enough ( Maybe shouldn't judge whether it is a tsBlock) The final conversion result of each compiler

import stylex from "@stylexjs/stylex";
export var X;
((X2) => {
  X2.styles = stylex.create({
    t: {
      color: "red"
    }
  });
})(X || (X = {}));

If we want to support namespace, then we should also support this.

[nmn]

If this is the output then this is not yet going to be feasible.

We can hoist up the generated objects to the top level of the module and replace the original stylex.create with a reference to that object. That way we can allow defining stylex.create anywhere you want.