reimplementation of official evaluate_qa.py that routes through the local antigravity proxy (127.0.0.1:8000/v1) instead of requiring OPENAI_API_KEY. same prompt templates and positional interface. - scripts/evaluate_qa_local.py: standalone script, nix-shell -p python3Packages.openai for deps, stream=True for SSE proxy compat - benchmarks/README.md: 'Official QA Evaluation (local judge)' section with --official-eval-cmd invocation for smoke (subset30) and full runs closes klbr-1yn (local judge available, no external dep needed) unblocks klbr-u3t