[keichi]

Node.js 22.12+ (and 20.19+) can require() ES modules without a flag, so the separate CommonJS build is no longer needed.

• Set "type": "module" and build once with tsc (module: nodenext) into dist/
• Remove the module field and the require/import conditions in exports
• Bump engines.node to >=22.12
• Update README to show import first

This also removes the dual package hazard (two copies of Parser when both formats get loaded) and the types mismatch where the ESM entry used CJS typings.

Verified locally: npm run build, npm test (166 passed), and both require("binary-parser") and import { Parser } from "binary-parser" resolve Parser on Node.

Since engines is raised, this should be released as a major version.