fix(review): exclude current branch from base branch picker#5

middleDuckAi wants to merge 4 commits intoupstream-main-20260324middleDuckAi/codex:upstream-main-20260324from

middleDuck/codex-12942-review-base-branch-picker-includes-currentmiddleDuckAi/codex:middleDuck/codex-12942-review-base-branch-picker-includes-currentCopy head branch name to clipboard