Improve RAG results via chunkHeader append (#1473)

...orkspaceChat/ChatContainer/ChatHistory/Citation/index.jsx

server/utils/TextSplitter/index.js

server/utils/vectorDbProviders/astra/index.js

server/utils/vectorDbProviders/chroma/index.js

server/utils/vectorDbProviders/lance/index.js

server/utils/vectorDbProviders/milvus/index.js

server/utils/vectorDbProviders/pinecone/index.js

server/utils/vectorDbProviders/qdrant/index.js

server/utils/vectorDbProviders/weaviate/index.js

server/utils/vectorDbProviders/zilliz/index.js