(Credit: Javier del Real / Teatro Real) Twenty years after its triumphant—and undeniably provocative—debut at the Salzburg Festival, Willy Decker’s “La Traviata” stormed the stage of Madrid’s Teatro Real. It is striking how a production that once shocked audiences has become a recognized classic, revealing its timeless, almost metaphysical essence. Premiered in 1853 at Venice’s Teatro La Fenice, “La Traviata” {…}