agent: Remove some unused code from the `Thread` (#39688)
This PR removes some unused code from the Agent1 `Thread`.
Release Notes:
- N/A
Co-authored-by: David Kleingeld <davidsk@zed.dev>
e765818487Marshall Bowers committed on 10/7/2025, 3:36:53 PM· committed by GitHubparent84f4888