Finalize notebook API (part 2)

[jrieken]

There is more API to be finalized

• the NotebookEditor API and its friends
• IPC for controllers and renderers
• various event for when notebook change etc

[bxantus]

Could you provide us with some updates regarding this issue?
It's really unconfortable for our users to use Insiders and opt-in for proposed APIs, so we use only the finalized APIs.

But without the NotebookEditor API I can't change metadata associated with the cells. Prepopulating the metadata from the NotebookSerializer when opening documents works, but only for existing cells...
I personally can't see why editing JSON compatible metadata can't be added to the final API. As I see it, the proposed API hasn't changed in a while in this regard...

[gjsjohnmurray]

The proposed API keyed on notebookEditor must also be enabled if an extension wants to contribute to the interactive/toolbar and interactive/cell/title menus, despite these being documented amongst finalized menu contribution points.

Also, the comment in vscode.proposed.notebookEditor.d.ts points to a stale closed issue. It would do better pointing here.

[mjbvz]

Now tracked by #149861