chore: Use langchain-spicedb v0.2.0 from PyPI instead of git ref

Author: sohanmaheshwar

agentic-rag-authorization/requirements.txt

@@ -2,7 +2,7 @@
 langchain>=0.1.0
 langchain-openai>=0.1.0
 langgraph>=0.0.20
-langchain-spicedb @ git+https://github.com/authzed/langchain-spicedb.git@main
+langchain-spicedb>=0.2.0
 weaviate-client>=3.26.0,<4.0  # v3 for REST API stability (no gRPC issues)
 authzed>=0.7.0
 python-dotenv>=1.0.0