Parent Document Retriever feature.

[radhakrishna67]

Expected Behavior

Lanchain's Parent Document Retriever feature is expected in Spring AI

Current Behavior
Files are chunked and cretead embeddings for them. We would like to have child chunks for parent chunks of the document.

[markpollack]

https://python.langchain.com/docs/modules/data_connection/retrievers/parent_document_retriever as a reference.

I'd like to have some RAG evaluation setup in place to better understand how things improve or not based on these types of algorithms. Putting in the backlog for now.

Contributions are welcome.