Improve public presentation

[HarperZ9]

Summary

• add a readable README hero rendered through the Telos product presentation config
• add public-facing why/test sections before technical framing
• add brand receipt docs with font/provenance/accessibility boundaries

Verification

• python tools/audit_repo_presentation.py --root C:\dev\public\agent-audit --root C:\dev\public\proof-surface --root C:\dev\public\secret-redact-io
• python -m pytest -q
• git diff --check
• changed-text secret-pattern scan