In an industry run by titans, a Singapore AI firm called Megaspeed International Pte. is drawing an unusual amount of attention. In less than three years, the once-obscure spinoff of a Chinese gaming enterprise has evolved into the single largest Southeast Asian buyer of Nvidia Corp. chips — a rapid ascent that’s lifted hopes for a regional champion in the lucrative business of AI cloud computing.Now Megaspeed finds itself a focal point of Washington’s long-held fears about semiconductor smuggli...