Add health report and golden command guardrails

[scottsgeorge]

Summary

• add HEALTH.md with repo scores, risks, CI/security/release assessments, and new baseline hygiene files (LICENSE, CODEOWNERS, .gitignore, .editorconfig)
• introduce root npm scripts for lint/test/build/start, document golden commands in README, and add webhook signature unit tests
• streamline CI to run the golden commands and remove the redundant CodeQL workflow

Testing

• npm run lint
• npm test
• npm run build

Remaining P0/P1 items

• lock JavaScript sample dependencies with per-sample lockfiles for reproducible installs
• add automation for the Python sample plus dependency/secret scanning in CI
• establish release/versioning guidance if any sample is to be reused or distributed

---

Codex Task

[chatgpt-codex-connector]

You have reached your Codex usage limits for code reviews. You can see your limits in the Codex usage dashboard.
To continue using code reviews, you can upgrade your account or add credits to your account and enable them for code reviews in your settings.