ROCHESTER — It’s been more than 20 years since Lanny Kolpek picked up a director’s baton to usher his students into harmony with one another, but by the time he retired in the mid-2000s, he’d had an impact on thousands of students over his 30 years teaching music in Rochester. And now, his family is gathering together the remnants of his long career as they say goodbye to one of Rochester’s longtime music men. Kolpek died on Tuesday, May 19, 202…