feat: preserve digest relay contract with audit persistence

[leether]

Purpose

Govern the six-file digest/relay change that was left uncommitted on an older
main, while preserving the audit persistence, CATALOG backlink, and draft
reconciliation behavior already merged in PR #13.

Root cause

The digest change and PR #13 both modified the orchestrator command builder and
its operator contract. Committing the older tree unchanged would have removed
the newer publish-evidence path even though the older tree passed its own tests.

Changes

• preserve the exact original dirty tree as a checkpoint commit
• merge current main and resolve overlaps as a behavior union
• pass digest plus audit/push-result/source/CATALOG arguments in relay commands
• retain automatic and manual relay paths
• renumber the overlapping Gotcha entries to unique G01-G38 identifiers
• keep the effective diff against main limited to the original six files

Validation

• npm run check
• ./scripts/privacy-check.sh --full
• git diff --check
• combined orchestrator command-contract assertions
• publish-evidence and reconciliation fixtures
• effective diff readback: exactly six governed files versus origin/main

No live WeChat draft creation or reconciliation write was performed.