CHICO, Calif. — Northern California crews battling the country’s deadliest wildfire in a century were bracing for strong winds Sunday that could erode gains they have made in containing the fearsome blaze, which has killed at least 76 and leveled a town. Even as hundreds of searchers sift through the rubble in the town of Paradise looking for the dead, nearly 1,300 people remain unaccounted for more than a week after the fire sparked in Butte County, Sheriff Kory Honea announced Saturday night.