从 iOS 17 Observation 迁移至 iOS 16 兼容的 Combine 架构

将最低部署版本降至 iOS 16，以 ObservableObject 替换 @Observable，新增导航与 UI 兼容层，并补充登录冒烟 UI 测试。

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

suixinkan/Features/Profile/Views/DebugHomeMenuPreviewView.swift

@@ -10,9 +10,9 @@ import SwiftUI
 
 /// 首页菜单调试预览页，展示所有已知菜单入口并跳过权限过滤。
 struct DebugHomeMenuPreviewView: View {
-    @Environment(AppRouter.self) private var appRouter
-    @Environment(RouterPath.self) private var router
-    @Environment(ToastCenter.self) private var toastCenter
+    @EnvironmentObject private var appRouter: AppRouter
+    @EnvironmentObject private var router: RouterPath
+    @EnvironmentObject private var toastCenter: ToastCenter
 
     private let items = HomeMenuRouter.debugAllMenuItems()