“Miracle in the Scrap Heap: The Sculpture of Richard Stankiewicz” at AXA Gallery until September 25 (The Equitable Building Atrium, 787 Seventh Avenue, at 51st Street, 212-554-2015). Rachel Harrison, Hirsch Perlman, Dieter Roth, Jack Smith, Rebecca Warren at Matthew Marks Gallery until September 13 (523 W. 24th Street, between Tenth and Eleventh Avenues, 212-243-0200) “A … Continued