Frolicking by a helicopter. Booty shorts. Makeup-free and stunning. Sitting on a photo-strewn floor, giddy after an all-nighter. That’s right, new mommy Beyoncé is back, and she’s spent the past month prepping for her comeback concert tonight at the grand opening of Revel resort and casino in Atlantic City. The just-released “making of” video doesn’t reveal too much, but we do know “Halo” — which Beyoncé hadn’t sung in over a year — is on the set list and that we can expect some good ol’ chair dancing, interpretive ballet, and fan-waving backup. But this is Beyoncé! She’d never give away the really good stuff.