Preheat the oven to 200°C (400°F). Use a sharp knife to prick the back of each wing, then pat wings dry with paper towels and arrange in a single layer on a parchment-lined baking sheet; sprinkle evenly with 1/2 teaspoon salt.
Bake the wings for 25 minutes, until lightly browned and cooked through.
While the wings bake, use a vegetable peeler to remove about 4 strips of lime zest and cut the lime in half; squeeze 2 tablespoons juice into a saucepan.
Trim and halve the scallions; add the white bottoms to the saucepan and reserve the green tops. Add the lime zest, entire bottle of Coca-Cola (16.9 oz), 1/4 cup soy sauce, smashed garlic, and sliced ginger to the pan.
Bring the cola mixture to a boil, then reduce heat and simmer uncovered for about 20 minutes, until reduced by about half and slightly thickened. Strain out solids and return the liquid to the pan.
In a small bowl, whisk 1 teaspoon cornstarch with 1 tablespoon water until smooth, then whisk into the hot sauce and cook for 3 minutes to thicken. Turn off the heat.
Pour half of the sauce into a large mixing bowl and stir in 2 tablespoons unsalted butter until melted and combined; reserve the remaining sauce for serving.
Remove baked wings from the oven and toss them in the buttered cola sauce until evenly coated, then return the wings to the baking sheet and bake for an additional 5 minutes, until dark golden brown and glossy.
Serve immediately with the reserved sauce on the side and garnish with chopped green scallion tops and a sprinkle of white sesame seeds if desired.