[Question]Issue with QueryFusionRetriever

[JacksonSun]

Hi team,
Recently i notice that a new QueryFusionRetriever class is being added to help realize the hybrid retriever. However, the _reciprocal_rerank_fusion function in QueryFusionRetriever seems not being implemented correctly.
In _reciprocal_rerank_fusion, the rank of the node given by the value of the score from nodes_with_scores in descending order. However, in some vector index store (like faiss), the return score is L2 distance according to the article here, where a lower score is better.

I have checked the results and notice after using the QueryFusionRetriever, the rerank results are in reverse order compared with original one.