@swc/core additional binding contracts that accept and receive utf8 data as JsBuffer instead of String

[dmichon-msft]

Describe the feature

If the caller prefers to delegate file reading to the NodeJS layer and/or has a custom workflow, it can save CPU cycles to pass the data into SWC directly as a UTF-8 encoded Buffer instead of transcoding the internal UTF-16 representation to UTF-8 (or vice versa).

My primary use case is with a flow where I:

1. Read raw text from disk to a Buffer
2. Call parse() and get back a serialized AST
3. Call transform() multiple times with different options, using the AST from (2)
4. Write the results to disk

All of the transfers between the NodeJS process and SWC would be more efficient if I could pass the data as Buffer instead of string.

Babel plugin or link to the feature description

No response

Additional context

No response

[kdy1]

We already support Buffer, including from swc-loader. Is it different thing?