Introduce unified design tokens and migrate Home, Orders, and Statistics UI.

Establish AppColor/AppFont/AppSpacing/AppRadius theming, shared components, and design-system docs so pilot screens align with Android while keeping iOS-native spacing and touch targets.

Co-authored-by: Cursor <cursoragent@cursor.com>

suixinkan/SceneDelegate.swift

@@ -16,6 +16,8 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
     ) {
         guard let windowScene = scene as? UIWindowScene else { return }
 
+        AppNavigationBarAppearance.applyGlobalAppearance()
+
         let window = UIWindow(windowScene: windowScene)
         window.rootViewController = AppRouter.makeRootViewController()
         window.makeKeyAndVisible()