Add Pyrefly LSP specification

[xaskii]

References

Closes #1136

Code changes

• Add LSP specification for Pyrefly: https://pyrefly.org/
• Exposes two settings also referenced in the package.json for the VS Code extension: https://github.com/facebook/pyrefly/blob/main/lsp/package.json

User-facing changes

• Exposes diagnostics and other LSP operations from Pyrefly

Notes

• Change in review for supporting didChangeConfiguration notifications with settings since Jupyter Lab doesn't use workspace/configuration requests
• Thanks for maintaining this project!

Chores

• linted
• tested
• documented
• changelog entry

[github-actions]

👈 Launch a binder notebook on branch xaskii/jupyterlab-lsp/add-pyrefly

[krassowski]

Once you rebase on main the CI failures should go away

[xaskii]

Thanks for fixing CI. I tried to follow the docs as faithfully as I can, but I'll try to respond quickly if anything needs to be changed.

[krassowski]

Thank you @xaskii! Thank you for the patience here.

The CI failure is unrelated and got addressed in #1150.

[krassowski]

@xaskii this was released in https://github.com/jupyter-lsp/jupyterlab-lsp/releases/tag/jupyter-lsp-2.3.0