Deny unknown keys in settings in JSON schema so user gets warnings but settings still parses (#30583)

Closes #ISSUE

Release Notes:

- Improved checking of Zed settings so that unrecognized keys show
warnings while editing them
ab455e1c43Ben Kunkle committed on 5/12/2025, 9:48:36 PM· committed by GitHubparent986d271
7 files changedLine totals unavailable