Updated CHANGELOG

Author: alexthomas93

CHANGELOG.md

@@ -7,6 +7,9 @@
 - Utility functions to retrieve metadata for vector and full-text indexes.
 - Support for effective_search_ratio parameter in vector and hybrid searches.
 - Introduced upsert_vectors utility function for batch upserting embeddings to vector indexes.
+- Introduced Neo4jMessageHistory and InMemoryMessageHistory classes for managing LLM message histories.
+- Added examples and documentation for using message history with Neo4j and in-memory storage.
+- Updated LLM and GraphRAG classes to support new message history classes.
 
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