chore: harden agent-eval release surface

[drewstone]

Summary

• fixes control-runtime failure reporting when trace emission also fails
• fixes knowledge readiness action selection for non-blocking gaps
• adds CallbackResearcher and tightens trace analyst / Ax adapter types
• publishes OpenAPI and benchmarks subpaths, removes raw examples from npm package, adds LICENSE
• aligns npm/Python versions at 0.20.9 and updates docs

Verification

• pnpm typecheck
• pnpm test
• pnpm build
• cd clients/python && PYTHONPATH=src python3 -m pytest
• npm pack --dry-run
• git diff --check