fix: Lock LangGraph version to <= 0.4.10

New version removed graph.graph we rely on.
temporarily fix the version before we fix the issue.

PiperOrigin-RevId: 776619611

Author: hangfei

pyproject.toml

@@ -95,7 +95,8 @@ test = [
   # go/keep-sorted start
   "anthropic>=0.43.0",               # For anthropic model tests
   "langchain-community>=0.3.17",
-  "langgraph>=0.2.60",               # For LangGraphAgent
+  # langgraph 0.5 removed langgraph.graph.graph which we depend on
+  "langgraph>=0.2.60, <= 0.4.10",    # For LangGraphAgent
   "litellm>=1.71.2",                 # For LiteLLM tests
   "llama-index-readers-file>=0.4.0", # For retrieval tests
   "pytest-asyncio>=0.25.0",