Kalshi Inc. withdrew announcements about a collaboration with Elon Musk’s artificial-intelligence firm xAI just hours after a top executive at the prediction markets firm touted the deal.Kalshi had announced on Tuesday morning that xAI would provide tailored information to offer guidance for bets made by the site’s users. By later that day, Kalshi had rescinded its statement, with a spokesperson for the firm explaining that “details of the announcement had not been mutually confirmed.”...