feat(cron): daily sync.source_doc enqueue

node-cron schedules runSync at 03:00 local time; runSync enqueues
sync.source_doc for every source_docs row with sync_source='url'.
Started from server.js's CLI gate alongside the job queue.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

package.json

@@ -18,6 +18,7 @@
     "jsdom": "^29.1.1",
     "marked": "^18.0.4",
     "multer": "^2.1.1",
+    "node-cron": "^3.0.3",
     "pg": "^8.21.0",
     "pg-boss": "^10.4.2",
     "pino": "^10.3.1",