fix IPython import for production

src/agent_graph/agent_backend.py

@@ -1,10 +1,14 @@
 import json
-from IPython.display import Image, display
 from typing import Annotated, Literal
 from typing_extensions import TypedDict
 from langchain_core.messages import ToolMessage
 from langgraph.graph.message import add_messages
 
+try:
+    from IPython.display import Image, display
+except ImportError:
+    pass
+
 
 class State(TypedDict):
     """Represents the state structure containing a list of messages.