Preheat oven to 400°F. Place hazelnuts on a baking sheet, and bake until toasted, 5 to 6 minutes. Coarsely chop nuts; place in a bowl. Stir in 1/4 teaspoon paprika and cayenne. Set aside. Heat oil in a large saucepan over medium. Add chard, parsley, cilantro, garlic, remaining 1 1/2 teaspoons paprika, cumin, and salt; cover and cook until chard is soft, about 8 minutes. Remove from heat. Stir together yogurt and lemon juice in a small bowl. Serve chard mixture at room temperature with a drizzle of yogurt sauce and a generous sprinkle of hazelnuts.