Llama-index-g

New Features
- add router module docs (7171)
- add retriever router (7166)

New Features
- Added a `RouterRetriever` for routing queries to specific retrievers (7166)

Bug Fixes / Nits
- Fix for issue where having multiple concurrent streamed responses from `OpenAIAgent` would result in interleaving of tokens across each response stream. (7164)
- fix llms callbacks issue (args[0] error) (7165)

New Features
- Added metadata filtering to weaviate (7130)
- Added token counting (and all callbacks) to agents and streaming (7122)

New Features
- Added `to/from_string` and `to/from_dict` methods to memory objects (7128)
- Include columns comments from db tables in table info for SQL queries (7124)
- Add Neo4j support (7122)

Bug Fixes / Nits
- Added `Azure AD` validation support to the `AzureOpenAI` class (7127)
- add `flush=True` when printing agent/chat engine response stream (7129)
- Added `Azure AD` support to the `AzureOpenAI` class (7127)
- Update LLM question generator prompt to mention JSON markdown (7105)
- Fixed `astream_chat` in chat engines (7139)

New Features
- Update `ReActAgent` to support memory modules (minor breaking change since the constructor takes `memory` instead of `chat_history`, but the main `from_tools` method remains backward compatible.) (7116)
- Update `ReActAgent` to support streaming (7119)
- Added Neo4j graph store and query engine integrations (7122)
- add object streaming (7117)

New Features

- Chat source nodes (7078)

Bug Fixes / Nits
- anthropic api key customization (7082)
- Fix broken link to API reference in Contributor Docs (7080)
- Update vector store docs (7076)
- Update comment (7073)