PARIS— Li Auto, a Beijing-based luxury carmaker, used this city’s auto show to show off a car with massage seats at the front, a 21-inch screen for passengers in the back and a unit in the central console that can keep your energy drink cool or your coffee warm. Meanwhile, BYD, the world’s bestselling electric-vehicle brand, took the veil off an SUV for Europe that can fill up much of a battery in five minutes. And not to be outdone, XPeng touted a test of autonomous-driving technology it conducted around the Arc de Triomphe, the 19th-century monument commissioned by Napoleon…