The New York City Ballet galas are famous, of course, for the performances by the dancers, but also for a blink-and-you-miss-it red carpet dash by Mick Jagger. The musician’s girlfriend, retired ballerina Melanie Hamrick, is a frequent attendee, so therefore Jagger has become one as well. On Thursday evening, at the NYCB Spring Gala, Hamrick was an event chair, with Jagger taking on the role of honorary chair. The duo joined Diane Kruger, Norman Reedus, Emmy Rossum, Hari Nef, Fran Drescher, Ashley Graham , Michael Bloomberg and more for an evening of cocktails, performance and dinner. Emmy Rossum was wearing a black and white sequined Julie de Libran slipdress for the occasion.  You May Also Like “I always like to feel comfortable and effortless. Even if it takes a little effort,” she said.…