Serves 6 to 8 INGREDIENTS ¼ cup lemon juice (from about 1 lemon) 2 teaspoons kosher salt 2 pounds large or extra-large shrimp, peeled and deveined 12 scallions (white and light green parts only), thinly sliced 1 cup fresh cilantro, chopped ½ teaspoon ground peppercorns 8 ounces capellini or angel hair pasta or thickly sliced…