Figure out and document how to use devcontainer with GitHub codespace

[joyeecheung]

I discovered that GitHub codespace also supports devcontainer.

https://github.com/nodejs/node/pull/60472#issuecomment-3467843933

This means for new Node.js contributors, they do not even need to download or install anything locally to start hacking on Node.js. Just click a few buttons on GitHub and they can start working on changes in the browser, and they can run tests in the container from the code space etc. as well. This might be very useful in code and learn sessions.

I don't know what extension codespace supports, but at least debugging the JS part of Node.js should be possible if the ports are set up correctly. One can always do command line debugging in the terminal in the code space as well. Or good old printing.

Codespace seems to be a paid feature but there's free tier available (?) so we'd be careful about directing people to it though

[bjohansebas]

Codespaces has a certain free limit for users who don’t have Pro, and Pro users get a few more hours. You can use it locally through this extension https://marketplace.visualstudio.com/items?itemName=GitHub.codespaces or you can use it in the browser. That’s how I use it when I’m building Node.js, since my machine isn’t very good and Codespaces is pretty fast.

There’s also an option at the organization level so that Codespaces billing is charged to the organization instead of the user, but this only works if you have write access to the repository and the organization has that option enabled.