web-platform-tests/wpt — reverse-engineered prompt

Build me a web platform testing project that helps browser makers and web developers check whether features work the same way in different browsers.

I want it to be a big organized test suite for things like HTML, CSS, DOM, cookies, storage, security, device APIs, media, and other web standards. It should let someone start a local test server, run selected tests in a browser, run a lint check, and update a test manifest from the command line.

Please include simple contributor docs so a new person can add a small test, run it locally, check it, and open a pull request. Also include a basic public documentation site style page that explains how to set up the repo, run tests, and find help.

Keep it practical and open source friendly. The goal is confidence that the same web feature behaves consistently across Chrome, Firefox, Safari, Edge, and other browsers. Look up current docs online if you need to.