Add enterprise webhook replay ledger

[FeeeeelixWong]

/claim #19

Summary

Adds a focused enterprise webhook delivery and replay ledger for the Enterprise Tooling bounty. This is intentionally narrower than another broad admin dashboard or export package: it validates signed institutional webhook envelopes, retry/dead-letter behavior, replay approvals, and delivery health evidence for enterprise integrations.

What is included

• Dependency-free webhook ledger core in enterprise-webhook-replay-ledger/src/webhook-ledger.js
• Synthetic enterprise integration data for DSpace, Canvas, ELN, and funder portal destinations
• Deterministic idempotency keys, body digests, and signing-key evidence
• Retry, dead-letter, replay-ready, and manual-review classification
• Replay plans with retention windows for failed delivery records
• Node test coverage and local CLI demo
• Requirement map for Enterprise Tooling #19
• Short demo video: enterprise-webhook-replay-ledger/docs/demo.mp4

Demo

The demo video shows degraded enterprise delivery health: DSpace and ELN deliveries succeeded, Canvas exhausted retries but has enterprise replay approval, and the funder portal is held for manual review before replay.

Verification

cd enterprise-webhook-replay-ledger
npm run check
npm test
npm run demo
ffprobe -v error -select_streams v:0 -show_entries stream=codec_name,width,height,duration -of default=noprint_wrappers=1 docs/demo.mp4

I also ran:

git diff --check -- enterprise-webhook-replay-ledger
rg -n "api[_-]?key|private[_-]?key|password|secret|token|wallet|ssn" enterprise-webhook-replay-ledger