By RICARDO CASTILLO     In mid-July, former Mexican Treasury Secretary Carlos Urzúa, upon presenting his resignation to President Andrés Manuel López Obrador (AMLO), launched a frontal attack against AMLO’s Chief of Staff Alfonso Romo Garza in an interview. “It’s most difficult to understand the type of relationship, ideologically speaking, Romo has with the president,” Urzúa said. “He’s an extreme right-winger.” Urzúa