Tighten chain-family output wording and proof boundaries

[TacoRocket]

Summary

• tighten chain-family operator wording so rows state visible facts and exact blocker types without speculative follow-up
• harden deployment-path and credential-path output, including calmer detail rows, better target/insertion wrapping, and stricter automation target mapping
• remove repo-local non-operator governance docs and keep the contribution guidance aligned with packaging-friendly repo hygiene

Validation

• python3 -m ruff check .
• python3 scripts/validate_publish_metadata.py --branch chain-output-truthfulness
• python3 -m pytest -m "not integration"
• git push -u origin chain-output-truthfulness