Improve branch selection UI for long branch names in the Codex app

Suggestion

I’ve run into a usability issue with the branch selector in the Codex app when branch names are long and similar.

Right now, long branch names are truncated in the branch dropdown. That becomes a real problem when multiple branches share the same prefix, because I can’t clearly tell which branch is which. There also doesn’t seem to be a hover state, tooltip, horizontal scroll, or any other way to view the full branch name.

As a result, selecting the correct branch becomes guesswork, especially in repositories that use long descriptive branch names.

I’m attaching a screenshot to show what I mean more clearly.