“Back erect! Chest up! Hips firm!” Carla Campos bawls over the wild tumult of samba drumming convulsing the speakers in her smart Ipanema dance studio. “Stop bobbing up and down! Stop wriggling! You’re not a chicken. You’re not a worm. You’re a man! You’re a malandro!” Ah, the malandro — the archetypal bad boy, the con artist, the…
