Bridgewater co-chief investment officer Greg Jensen is a big believer in AI's potential.WEFMultiplier, formerly known as WithAI, is a young AI company that works with hedge funds' stockpickers.The firm raised $6 million from Y Combinator, Lux Capital, and Bridgewater's chief investment officers, among others.The firm is run by a former Bridgewater investment associate, Ian McInnis.Smaller hedge funds outgunned by deep-pocketed rivals believe art…