The Apple Inc. executive leading an effort to develop AI-driven web search is stepping down, marking the latest in a string of high-profile exits from the company’s artificial intelligence division.The executive, Ke Yang, is leaving for Meta Platforms Inc., according to people with knowledge of the matter. Just weeks ago, he was appointed head of a team called Answers, Knowledge and Information, or AKI. The group is developing features to make the Siri voice assistant more ChatGPT-like by adding...