Pass metric type to vector search function

Thanks Josh; I think we should probably pass something more generic to avoid further interface changes in the future though. If for example we pass the QueryInterface you can then access the query, index, and server. So in your case I believe $query->getIndex()->getServerInstance()->getBackendConfig() should contain the metric.

Also latest phpcs changes use statement order, so test coverage is failing.

@joshhytr this issue was flagged is important for [Meta] Bring AI Search out of Experimental 🌱 [Meta] Bring AI Search, Assistants and Chatbot out of Experimental Active . We would like to have it fixed until 4th February 2025. Will you manage or are you happy for maintainers to help?

Thanks @seogow, thanks @scott_euser.

I've updated the MR with the suggested change and have been able to obtain the metric_type from the query as required.