git_ui: Fix Enter key selecting branch in commit modal branch picker

[saberoueslati]

Context

When the "Switch branch" picker is opened from the git commit modal and the user presses Enter, a \n character was inserted into the input instead of confirming the branch selection.

The "GitCommit > Editor" keymap context bound enter to editor::Newline. This context matches any Editor descended from GitCommit in the element tree, including the single-line search editor inside the branch picker popover. Because a context-path binding is more specific than the global enter: menu::Confirm binding, it took precedence and the picker never received the confirm action.

The commit message editor uses EditorMode::AutoHeight (reported in key context as mode == auto_height); the picker's search editor uses EditorMode::SingleLine. Narrowing the context to "GitCommit > Editor && mode == auto_height" restricts the editor::Newline binding to the commit message editor only. Single-line editors inside the same modal now fall through to the global enter: menu::Confirm, which correctly confirms the selection.

Closes #58022

How to Review

Three identical one-line changes, one per platform keymap (default-linux.json, default-macos.json, default-windows.json):

• "GitCommit > Editor" → "GitCommit > Editor && mode == auto_height"

Video of manual test after fix :

Screencast.from.2026-06-02.23-16-32.webm

Self-Review Checklist

• I've reviewed my own diff for quality, security, and reliability
• Unsafe blocks (if any) have justifying comments
• The content is consistent with the UI/UX checklist
• Tests cover the new/changed behavior
• Performance impact has been considered and is acceptable

Release Notes:

• Fixed Enter key inserting a newline instead of selecting a branch in the commit modal branch picker

[ChristopherBiscardi]

the mode as a selector feels a bit awkward, but what's more awkward is that we even let users change the branch during a git commit, which is a weird operation in my opinion. I can't think of a good reason to change a branch while mid-commit message, but that's not this PR's problem.

This PR does fix the issue, thanks!

[saberoueslati]

@ChristopherBiscardi Here is my 2 cents on what you spoke of.

I agree on most of what you said but one caveat, I change branches right before a commit for just one use case, when I'm working on an issue I usually work on branch main or master then right before a first commit I create a branch for the change and commit there, maybe what would make more sense there is a button that would let you just create a new branch that you switch to then you write your commit message and commit, a button that might be similar in shape and functionality to what appears in the screenshot you put in your comment.