update to pyodide 0.26.0

[bollwyvl]

references

• for #108

changes

• [x] update to jupyterlab 4.2.1
• [x] update to jupyterlite-core 0.4.0a3
• [x] fix some docs warnings (pygment_ -> pygments_)
• [x] update compatibility table
• [x] basic local smoke testing
• [ ] investigate applicable new pyodide/micropip features
  • [x] run_sync to remove await input needs feature flag in nightly chrome
  • [ ] ???

[github-actions[bot]]

:point_left: Try it on ReadTheDocs

[bollwyvl]

RTD notes:

• it's nice to get the brotli-compressed wheels for e.g. IPython