新增宣传页 Mock 模块并接入首页路由。

从 xh_test 同步 ScenicPromotion 演示页，补齐 MVVM 结构、本地资源、单元测试与模块文档，注册 promotion_page 首页入口。

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

suixinkan/Features/Home/Views/HomeIconCatalog.swift

@@ -56,6 +56,8 @@ enum HomeIconCatalog {
             "mappin.circle.fill"
         case "report_photographer":
             "shield.fill"
+        case "promotion_page":
+            "rectangle.on.rectangle.angled"
         case "registration_invitation", "photographer_invite":
             "envelope.open.fill"
         case "store":