refactored color to surface

Signed-off-by: Matt Bruce <matt.bruce@verizon.com>

VDS/Components/Toggle/VDSToggle.swift

@@ -377,7 +377,7 @@ import Combine
             }, completion: nil)
         }
         
-        backgroundColor = viewModel.surface == .dark ? VDSColor.backgroundPrimaryDark : .clear
+        backgroundColor = viewModel.surface.color
         isUserInteractionEnabled = !viewModel.disabled
         
         setAccessibilityHint(enabled)

VDS/Protocols/Surfaceable.swift

@@ -6,9 +6,14 @@
 //
 
 import Foundation
+import UIKit
+import VDSColorTokens
 
 public enum Surface: String, Codable {
     case light, dark
+    public var color: UIColor {
+        return self == .dark ? VDSColor.backgroundPrimaryDark : .clear
+    }
 }
 
 public protocol Surfaceable {