feat: add evidence intake checklist

[stevenchouai]

Summary

• Adds a static evidence intake checklist for preparing public-safe agent traces before scoring
• Links the checklist from the root README and public reports README
• Adds regression coverage so the page stays static, linked, and privacy-aware

Test plan

• python -m unittest discover -v
• git diff --check
• Added-line privacy/static scan for emails, secrets, local paths, external URLs, and scripts