SAN FRANCISCO — Mehul Agarwal, a co-founder of the artificial intelligence startup Koyal, has a goal. He wants to find a wife before he gets rich.The 24-year-old says he wants to be loved before the money comes so he never has to wonder whether a partner is attracted to him or his success. But he has strict criteria. A potential girlfriend must be smart — “someone who went to Stanford or MIT is great” — and beautiful, which he is careful to distinguish from “hot,” a term he considers shallow. She must be kind and in possession of a personality,…