remove NATS integration

examples/smartreceive_example.rs

@@ -2,7 +2,7 @@ use msghandler::{smartreceive, SmartreceiveOptions};
 
 #[tokio::main]
 async fn main() {
-    // Simulated NATS message JSON (received from NATS subscription)
+    // Simulated message JSON (received via any transport)
     let msg_json_str = r#"{
         "correlation_id": "abc123-def456-ghi789",
         "msg_id": "msg-uuid-001",
@@ -15,7 +15,7 @@ async fn main() {
         "receiver_id": "",
         "reply_to": "/agent/wine/api/v1/response",
         "reply_to_msg_id": "",
-        "broker_url": "nats://localhost:4222",
+        "broker_url": "localhost:4222",
         "metadata": {},
         "payloads": [
             {