Support for Pinecone hybrid search

[kpzen]

Checked

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Feature request

Pinecone offers a hybrid search option, combining vector and keyword search. This feature is supported in the python version, but not langchainjs, and it would be a good addition since it offers better results.

See: https://python.langchain.com/docs/integrations/retrievers/pinecone_hybrid_search/

Motivation

Hybrid search offers better results than pure vector or keyword search, especially in out of domain areas.

Proposal (If applicable)

No response