It’s the final week of the Salzburg Festival, but before it concludes “Lucrezia Borgia” will open in two concert performances with a stellar cast that includes Juan Diego Flórez and Ildar Abdrazaov with Marco Armiliato conducting. But it is Krassimira Stoyanova that headlines the performances in the title role and forays once again into the Bel Canto repertoire. Throughout her career Stoyanova has {…}