“Slick,” “animated energy,” “playful,” “strangely compelling,” “very silly,” etc. As expected, 21 Jump Street (Sony, 3.16) is doing well by critics. But before this sank in I had a moment of…slight alarm when an invitation arrived yesterday to the 3.12 all-media screening in Manhattan. “Columbia Pictures Invites you and your family to a screening of 21 Jump Street,” it said. The invitation to the LA all-media didn’t use the “f” word so I figured the New York invitation was just an odd flourish.