fix: resolve LiteLLM initialization issues in math and calc servers

- Updated initialization logic in `math_server.py` and `calc_server.py`
- Addressed missing or invalid response output due to improper model handling

examples/mcp_example/calc_server.py

@@ -29,5 +29,5 @@ def percentage(value: float, percent: float) -> float:
 
 if __name__ == "__main__":
     print("Starting Calculation Server on port 6275...")
-    llm = LiteLLM()
+    llm = LiteLLM(system_prompt="You are a financial calculation expert.")
     mcp.run(transport="sse", host="0.0.0.0", port=6275)

examples/mcp_example/math_server.py

@@ -66,5 +66,5 @@ def divide(a: float, b: float) -> float:
 
 if __name__ == "__main__":
     print("Starting Math Server on port 6274...")
-    llm = LiteLLM(model_name="gpt-4o-mini")
+    llm = LiteLLM()  # This will use the default model
     mcp.run(transport="sse", host="0.0.0.0", port=6274)