[transformer] bundle runtime helpers / remove runtime helper import code from output

[sapphi-red]

I'm trying to use the transform api as a replacement of esbuild.transform. When esbuild needs to use a helper function for lowering, it injects them at the top of the output (esbuild try).
On the other hand, oxc injects a import or require for the helper function.

This makes it difficult to use it as an replacement for my case. I'm running esbuild in renderChunk hook of rollup and at that time the chunking has already done. I have to analyze the output and run a different build to get the helper functions and connect the chunks.

If oxc has a flag that injects the helper function into the output, it will be really easy to swap esbuild with oxc.

Or if oxc has a flag that makes the output to not include the import/require, I won't need to analyze the output.
An example API looks like this:

const result = transformWithOxc(name, 'const bar = {..."bb"}', {
  target: 'es2017',
  sourceType: 'module',
  helpers: 'external' // proposed flag
})

console.log(result.helpers) // { '_objectSpread': '@babel/runtime/helpers/objectSpread2' }

Then, I can know which helpers are needed without analyzing the output.