CoreWeave (CRWV) reported a smaller-than-expected, second-quarter loss amid operating margin improvement. Revenue topped estimates amid strong demand for artificial intelligence computing infrastructure. CoreWeave stock jumped on Wednesday. The Nvidia (NVDA)-backed company reported Q2 earnings after the market close on Tuesday. In the quarter ending June 30, CoreWeave said it lost $1.14 per share vs. a 60-cent loss a year earlier.…