runtime: resolve side-repo checkout/branch correctly for push_to_pull_request_branch when origin/HEAD is unset#48786

pelikhan merged 12 commits into

maingithub/gh-aw:mainfrom

copilot/runtime-push-to-pull-request-fixgithub/gh-aw:copilot/runtime-push-to-pull-request-fixCopy head branch name to clipboard