lavinmq's runtime container runs its provisioner

The runtime container named no command, so it ran the image default —
the tool host — and the provisioner entrypoint compiled beside it never
ran anywhere: no vhost was ever minted, while the grants sat applied in
its mounted directory. postgres already names its provisioner in args;
lavinmq now does the same. Surfaced by the built-store-cross-node bed,
run 9 — the first bed to reach the vhost assertion honestly.

modules/lavinmq/module.json

@@ -107,7 +107,11 @@
         "MESH_PROVISION_LAVINMQ": "http://127.0.0.1:15672",
         "MESH_PROVISION_ADMIN_USER": "guest",
         "MESH_LAVINMQ_ADMIN_PASSWORD": "guest"
-      }
+      },
+      "args": [
+        "run",
+        "/app/modules/lavinmq/dist/provisioner/index.js"
+      ]
     }
   ],
   "build": {