NEW YORK — Remember Donna Karan’s “cold shoulder” dresses that attracted so much attention a few years back? Karan does. And she still maintains that the shoulder is “one of the sexiest parts of a woman’s body.” This fall, Karan bares it again, in sweaters that drape the body in luxurious cashmere. Here, from the collection she will show on Friday, the languid sweater over a silk tulle camisole and relaxed wool crepe pants. For more on the New York collections, see pages 6 to 9.