By Pat Padua, Special To The Washington Post Actress Kristen Stewart may forever be associated with the popular “Twilight” franchise, movies that center on the growing pains of vampires and werewolves. Lately, however, she has shone in more serious fare from such directors as Woody Allen (“Cafe Society”) and Kelly Reichardt (“Certain Women”). With her latest film, French director Olivier Assayas’s “Personal Shopper,” Stewart returns to the kind of supernatural themes that made her a star at the multiplex — only this time it’s in a stylish, highly entertaining art-house thriller. Stewart plays Maureen, a personal shopper in Paris who buys expensive clothing for her busy celebrity client (Nora von Waldstätten).