(Ruth Fremson | The New York Times) A display of handguns at Sharp Shooting Indoor Range & Gun Shop in Spokane, Wash., Nov. 4, 2019. A year after the coronavirus pandemic began, the toll of self-inflicted gun deaths has led to an unusual alliance between suicide-prevention advocates and gun-rights proponents; together they are devising new strategies to prevent suicide in a population committed to the Second Amendment and the right to bear arms.