First CI run confirmed winvm-builder is a self-hosted act_runner labeled "windows-latest" but not the GitHub-hosted windows-latest image -- cmake isn't on PATH there (unlike the Linux/macOS runners, which do have working system/brew package managers). Use lukka/get-cmake to fetch a pinned cmake+ninja without needing admin/choco. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01RL8abRmgFXkVASHkkqiJbE