Next week La Scala reopens in its refurbished home. “At first glance, little has changed in 226 years — not the terraced neoclassical facade designed by architect Giuseppe Piermarini, nor the intimate, semicircular theater. Yet hovering discreetly behind the 18th-century exterior today are a tubular structure and a multistoried fly tower, both very 21st century. They were designed by Mario Botta, architect of the San Francisco Museum of Modern Art, to update and expand the opera’s backstage area in a 60.5 million euro ($80.6 million) revamp that opera professionals say was long overdue.”