Better levels

Sources/OpenFoodFacts/Schemas/NutrientLevels.swift

@@ -4,10 +4,20 @@ public struct NutrientLevels: Codable, ObjectDebugger {
 	public var saturatedFat: String? = nil
 	public var sugars: String? = nil
 
-	private enum CodingKeys: String, CodingKey {
+	public enum CodingKeys: String, CodingKey {
 		case fat
 		case salt
 		case saturatedFat = "saturated-fat"
 		case sugars
 	}
+
+	public subscript(_ key: CodingKeys) -> String? {
+		switch key {
+		case .fat: fat
+		case .salt: salt
+		case .saturatedFat: saturatedFat
+		case .sugars: sugars
+		}
+	}
+
 }