JupyterLite plugin for MySTMD and/or JB2

[agriyakhetarpal]

This is being discussed with the "Interactive tutorials" work group at the time of writing. The idea is to port a subset of the functionality (for the notebooks, that is – not for interactive examples) from https://github.com/jupyterlite/jupyterlite-sphinx/ to run with the MyST Document Engine as an "Executable Plugin", such that MyST can run JupyterLite.

Things to take note of:

• do we install the Pyodide kernel's npm package? How do we integrate a Python dependency in a JS stack?
• how to add Sphinx-Gallery-like buttons? In my experience, this is best handled by CSS, but that only controls their position and not addition. @bsipocz and @rossbar mentioned that an "Open in Binder" button exists already, which might be worth checking out.
• this is opposed to in-page configuration with Thebe

[bsipocz]

We do use open in binder launch button, and I also started using thebe with one of my other downstream repos. So far that experience is not bad, but some people still complain about the slowness of the binder startup.

[rootsmusic]

Interactive tutorials are of interest beyond this community. So I thought a dormant repo (for an outdated open-sourced book) may be relevant to the work group.