CHICAGO — Red and white pinstripes line the walls, as multicolored balloons hover above the group of magicians, contortionists and jugglers hard at work. Sticky fingers and faces wander about with sugar-fueled smiles, parents in tow. While you might assume that you’ve stumbled into the circus, you’d only be about half-right. In reality, you’ve happened upon Sideshow Gelato — a new Lincoln Square gelato shop with a niche twist. Each of the “scoopers” are young performers honing their sideshow acts. While serving gelato, they sharpen their juggling, magic and performance skills before customers....