Explore support for `notebook.codeActionsOnSave`

[Yoyokrazy]

• list of user adjustable actions that happen just before save
• integrate alongside formatOnSave
• features:
  • notebook specific features
    • move all imports to top
    • delete empty cells
  • language server has things?
  • linting?

[Yoyokrazy]

merge all code with %pip install ... to a new top cell?

[jrieken]

• rule: source action can only modify its file (text document or notebook) @Yoyokrazy
• code action kind for notebooks: source.notebook.xyz or notebook.source.xyz or notebook.xyz @Yoyokrazy
• register code action provider for notebookType @Yoyokrazy
• notebook on save: (1) call notebook-provider with first cell (2) call code providers for documents @Yoyokrazy

[Yoyokrazy]

#182799 adds support for standard CodeAction providers to supply actions for notebook cells, also ensures that edits only apply to the given cell via a check between the TextEdit's resource and the model URI. Existing providers and extensions may need a document selector/filter capable of selecting notebook cells.

notebook on save: (1) call notebook-provider with first cell (2) call code providers for documents

Part (2) of this statement is now completed. This CodeAction sorting will need to be revised to prioritize the Notebook CodeAction type, rather than source.fixAll. Current thinking is that this should take priority over the parallel cell actions, as Notebook types will likely restructure the contents of multiple cells.

code action kind for notebooks: source.notebook.xyz or notebook.source.xyz or notebook.xyz

Current thought is to adopt notebook.xyz for actions affecting the entire notebook. Actively working on an extension to experiment with functionality