chore: use latest dependencies for agui fastapi example

Author: ranst91

typescript-sdk/integrations/langgraph/python/ag_ui_langgraph/examples/poetry.lock

@@ -8,7 +8,7 @@ packages = [{ include = "agents" }]
 
 [tool.poetry.dependencies]
 python = "<3.14,>=3.10"
-ag-ui-langgraph = { version = "0.0.2", extras = ["fastapi"] }
+ag-ui-langgraph = { version = "0.0.3", extras = ["fastapi"] }
 python-dotenv = "^1.0.0"
 fastapi = "^0.115.12"
 uvicorn = "^0.34.3"