Java: Use functions/stored procedures for calculating similarity #60

The implementation of the memory nearest match API computes cosine similarity on the client side.
Is it possible to compute cosine similarity on the database side through a database function or stored procedure?
If so, withEmbeddings could be pushed to the database side (i.e., should the embeddings column be selected?)

• Could sorting and limiting be done on the database side, too?
• Is the extra overhead on the database a good tradeoff for less overhead in data on the wire?