This cloud be just what you want.

import { text } from "node:stream/consumers";

console.log(await text(process.stdin));

streamConsumers.text(stream) (nodejs.org)

streamConsumers.text(stream)

Added in: v16.7.0

• stream <ReadableStream> | <stream.Readable> | <AsyncIterator>
• Returns: <Promise> Fulfills with the contents of the stream parsed as a UTF-8 encoded string.