Cut the test environment over to the 3-node Proxmox NATS cluster.

Fleet/keep/middleware NATS_URL lists 10.10.10.21–23. Product streams
are replicas=3. px-worker worm/tree run on that cluster. Backup timer
and px-worker uptime watch are on. MOCK_VERAE and Zapier push unchanged.

packages/verae-zapier-middleware/src/nats/connection.js

@@ -78,7 +78,7 @@ export async function ensureStreams(manager) {
         retention: 'limits',
         storage: 'file',
         max_age: 24 * 60 * 60 * 1e9, // 24h in ns
-        num_replicas: 1,
+        num_replicas: Number.parseInt(process.env.JETSTREAM_REPLICAS || '1', 10) || 1,
       });
       log.info('stream created', { stream: def.name, subjects: def.subjects });
     }