Working branch

[Riingbuffer]

This merge request introduces several enhancements aimed at improving our library for the PV211 course. The primary goal of these changes is to support student learning by providing clear, easy-to-understand code that students can build upon and extend.
Summary of changes:

• Query Expansion for Retriever: Enhances the retriever with query expansion functionality to improve retrieval effectiveness.
• New Ranker Class: Introduces a new Ranker class, which is conceptually similar to the previous Reranker. The new name better reflects its functionality. It leverages a vector database, significantly improving performance.
• Interleave Method: Adds an interleaving strategy using a round-robin approach to combine results from multiple sources.

The focus throughout is on clarity, simplicity, and educational value.

[stefanik12]

Hi @Riingbuffer,
Thanks for extending the functionality of pv211-utils!

My problem with adding a functionality dependent on new external libs (faiss-cpu) is that we don't have a docker image where we know that students can run this. Introducing a new dependency into pv211-utils without building a new docker image can get us into a situation where the students will not be able to install the pv211-utils at all and the whole project will get stuck.

To be able to move forward with this, we need to fix the current CI that takes care of building the docker, or to build a docker image for running the tests manually. Not sure what is your experience with CI (continuous integration pipelines, e.g. here and currently failing here). If you would know how to do something with it, I can add you as a developer of the project and you can play around with it (on a separate branch). If you would not really know how to move forward with this, I am afraid that your PR will have to wait until someone else fixes the pipeline.