A Grass Valley woman has been arrested on suspicion of arson in the wake of a fire that caused major damage to a building in downtown Grass Valley Wednesday night. One apartment unit sustained major damage, but no one was hurt in a fire that started in the two-story building next to Grass Valley’s city hall late Wednesday. The fire was reported around 8:40 p.m. and involved a residence behind City Hall and the police station in the 100 block of Stewart Street that was subdivided into nine apartments housing 16 occupants, said Grass Valley Fire Chief Tony Clarabut. Grass …