MIAMI — When the pool deck at Champlain Towers South collapsed early on the morning of June 24, the building’s fire alarm system quickly sent out a distress signal to its alarm company. It was 1:15 a.m. — seven minutes before half of the 12-story tower came crashing down and killed 98 people. But in that crucial seven-minute span between the pool deck collapsing and the tower failing, no klaxons, sirens or warnings seem to have gone off in the building’s condo units, hallways or lobby, according to a review of audio and video footage and interviews with more than a dozen residents and workers ...