A nine-alarm fire tore through a brick apartment building in Allston on Wednesday night, injuring five firefighters and two bystanders and displacing more than 50 people, officials said. Firefighters rushed to 8, 12, and 16 Harvard Terrace at 5:47 p.m. and found heavy fire on arrival, authorities said. Flames burst through the roof, and officials ordered all firefighters out of the building, located near a busy intersection with Brighton Avenue.