assistant edit tool: Reliability improvements (#27431)

- Add instructions in description to read before editing
- Add instructions in edit prefix to explicitly ask for reads
- Fix `connection error: delay between messages too long` by processing
chunks off a channel

Release Notes:

- N/A
408e157d0fAgus Zubiaga committed on 3/25/2025, 3:34:01 PM· committed by GitHubparent2414855
3 files changedLine totals unavailable