Update nova_agent.py

nova_agent.py

@@ -28,7 +28,7 @@ class NovaProAgent:
             region_name='us-east-1'
         )
 
-        self.model_id = "amazon.nova-pro-v1:0"
+        self.model_id = "amazon.titan-text-lite-v1"
         self.content_type = "application/json"
         self.accept = "application/json"