align notebook agent change save behavior with text files

[amunger]

• auto save after making a change to a notebook file
• prevent normal auto saving while a change is streaming in

[vs-code-engineering]

📬 CODENOTIFY

The following users are being notified based on files changed in this PR:

@jrieken

Matched files:

• src/vs/workbench/contrib/chat/browser/chatEditing/chatEditingModifiedNotebookEntry.ts

[Copilot]

Pull request overview

This PR aligns chat-driven notebook editing behavior with how text-file chat edits behave in the workbench: it disables normal auto-save while incremental edits are streaming in, and triggers an auto-save once the final edit batch has been applied.

Changes:

• Track “waiting for last edits” for notebooks during streamed agent edits to temporarily disable normal auto-save.
• Auto-save the notebook (skipping save participants) after the final notebook edit batch is applied.
• Add a unit test asserting the final-edit auto-save behavior.

Show a summary per file

File	Description
src/vs/workbench/contrib/chat/browser/chatEditing/chatEditingModifiedNotebookEntry.ts	Sets _waitsForLastEdits during streaming and triggers an AUTO save (skipping save participants) on the final edit batch for non-untitled notebooks.
src/vs/workbench/contrib/chat/test/browser/chatEditing/chatEditingModifiedNotebookEntry.test.ts	Adds coverage verifying the notebook entry invokes save({ reason: AUTO, skipSaveParticipants: true }) on the final edit batch.

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 0