fix: harden queue lifecycle and publish gate

- Preserve phase results on partial retry and keep interrupted phase
  context after restart.
- Avoid webhook bookkeeping crashes when retention deletes stale jobs.
- Add deeper unit, integration, and e2e coverage around queue seams.
- Require verify job to pass before publish runs.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

README.md

@@ -11,6 +11,8 @@ Framework-agnostic async job queue for Node.js with:
 - **Retention cleanup** for stale and expired jobs
 - **ESM-only**, **Node 20+**
 
+Detailed architecture and runtime docs live in [`docs/`](./docs/README.md).
+
 ## Install
 
 ```bash