Closes #13304 Release Notes: - Add global `git status` and `git diff` on/off in one place instead of control everywhere We can first review to ensure this change meets both `Zed` and user requirements, as well as code rules. Currently, we only support user-level settings. We can wait for this PR: https://github.com/zed-industries/zed/pull/43173 to be merged, then modify it to support both user and project levels.