fix: worker waits for schema before claiming; npm ci for reproducible builds

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

worker/tests/test_db.py

@@ -0,0 +1,11 @@
+from lyra_worker.db import wait_for_db
+
+
+def test_wait_for_db_returns_usable_connection_when_schema_ready(conn):
+    # `conn` fixture guarantees the DB is up and the schema is migrated.
+    result = wait_for_db(timeout=5)
+    try:
+        with result.cursor() as cur:
+            cur.execute('SELECT 1 FROM "Job" LIMIT 0')
+    finally:
+        result.close()