MANEBHANJYANG, Nepal — On a steep slope in the foothills of the Himalayas one recent afternoon, Omnath Timilsena surveyed what remains of his earthquake-ravaged village in Nepal. By Mr. Timilsena’s estimate, four-fifths of the buildings were flattened or damaged beyond repair by the April 25 temblor. That used to be the schoolhouse, he said, pointing to a...