Just eight weeks ago, Saks Fifth Avenue was celebrating the return of its annual holiday lights display at its Manhattan flagship store. The splashy November premiere, complete with an appearance by the Radio City Rockettes, appeared to be a positive sign for the fortunes of the embattled retailer. The previous year, Saks had canceled its holiday light show as part of an effort to cut costs. Now, however, Saks’ glittery tribute to diamonds and shopping looks more like a last hurrah than a