fix(deploy): reuse shared server n8n

docs/17-runbook.md

@@ -62,6 +62,29 @@ curl -b cookies.txt http://localhost:8128/api/v1/workflows | grep succeeded
 A failed/offline n8n does not roll back the return — the outbox event simply stays
 `pending`/`failed` and is safely retryable from the Automation page.
 
+### Existing shared n8n on the Unraid review server
+
+The Unraid deployment uses the existing n8n at `http://192.168.10.150:5678`; it does not
+start MobilityOps's bundled n8n service. `compose.unraid.yaml` places that fallback behind
+the opt-in `bundled-n8n` profile. Configure the API target and publish the workflow with:
+
+```bash
+sed -i \
+  's|^N8N_WEBHOOK_URL=.*|N8N_WEBHOOK_URL=http://192.168.10.150:5678/webhook/mobilityops-return|' \
+  .env
+./deploy/unraid/setup-existing-n8n.sh \
+  n8n \
+  http://192.168.10.150:1236/api/v1/integrations/n8n/return-callback
+docker compose -p mobilityops -f compose.yaml -f compose.unraid.yaml up -d db api web
+```
+
+The setup script reads the callback token from the mode-0600 deployment `.env`, builds and
+removes a temporary server-side import without writing the token to Git, and restarts the
+existing n8n so the production webhook is registered. The imported configuration remains
+inside n8n's protected application data. The callback travels through the MobilityOps web
+proxy, so the shared n8n container does not need direct database access or membership of
+the MobilityOps Docker network.
+
 ## Required operational checks
 
 - API and web health (`GET /health`, web root `200`);

docs/design/implementation-validation.md

@@ -66,8 +66,10 @@ The same widths are automated in `frontend/e2e/ui-redesign.spec.ts`.
 - Authenticated network verification through the deployed web proxy returned HTTP 200
   for dashboard, vehicles, active booking, open quality issues, knowledge status,
   workflows and audit.
-- Container verification: PostgreSQL and API healthy, web HTTP 200, n8n `/healthz`
-  returned `{"status":"ok"}`. Existing database and n8n volumes were preserved.
+- Container verification: PostgreSQL and API healthy, web HTTP 200, and the server's
+  existing n8n on port 5678 returned healthy. No second MobilityOps n8n container is
+  running. A synthetic return completed the shared-n8n callback on attempt 1 and the demo
+  was reset to its deterministic start state.
 
 ## Performance choices