NEW YORK — A 3-year-old boy plummeted to his death from the 29th-floor balcony of a Manhattan high-rise on Saturday morning, police said. The child fell from the Taino Towers complex in East Harlem around 11 a.m., landing on the third-floor scaffolding with a sickening thud before he was rushed to Harlem Hospital and pronounced dead, authorities said. “We heard a big bang,” said Richard Linares, 36, who was at the heartbreaking scene on E. 122nd St. “My boy that was here ran to the front. He ran up the scaffold to find the baby. The baby was still crying and breathing when he got there. “By th...