Closes [#41674](https://github.com/zed-industries/zed/issues/41674) Description: Creating a branch from a base requires switching to the base branch first, then creating the new branch and checking out to it, which requires multiple operations. Add base_branch parameter to create_branch to allow a new branch from a base branch in one operation which is synonymous to the command `git switch -c <new-branch> <base-branch>`. Below is the video after solving the issue: (`master` branch is the default branch here, and I create a branch `new-branch-2` based off the `master` branch. I also show the error which used to appear before the fix.) [Screencast from 2025-11-07 05-14-32.webm](https://github.com/user-attachments/assets/d37d1b58-af5f-44e8-b867-2aa5d4ef3d90) Release Notes: - Fixed the branch-picking error by replacing multiple sequential switch operations with just one switch operation. Signed-off-by: ayu-ch <ayu.chandekar@gmail.com>