Nehemiah was almost a year sober. The young man known to friends as Nemo had come to Art Dahlen’s Battlefield Addiction sober-living home in Kent with legal troubles and a desire to get clean. He stayed. He worked the program. He was building something. On the morning of May 28, Dahlen took a crew from Battlefield out to a client’s property to do yard work. It’s one of the ways the program raises money. Nemo asked to stay behind, and Dahlen trus…