Migrate from iOS 17 Observation to iOS 16-compatible Combine architecture.

Lower deployment target to iOS 16, replace @Observable with ObservableObject, add navigation and UI compatibility shims, and include login smoke UI tests.

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

suixinkan/Features/Profile/ViewModels/ProfileViewModel.swift

@@ -6,21 +6,20 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 @MainActor
-@Observable
 /// 个人信息页 ViewModel，负责资料加载、编辑状态和提交更新。
-final class ProfileViewModel {
-    var userInfo: UserInfoResponse?
-    var realNameInfo: RealNameInfo?
-    var isLoading = false
-    var isSaving = false
-    var isEditingProfile = false
-    var editingNickname = ""
-    private(set) var pendingAvatarData: Data?
-    private(set) var pendingAvatarFileName: String?
-    private(set) var avatarUploadProgress: Int?
+final class ProfileViewModel: ObservableObject {
+    @Published var userInfo: UserInfoResponse?
+    @Published var realNameInfo: RealNameInfo?
+    @Published var isLoading = false
+    @Published var isSaving = false
+    @Published var isEditingProfile = false
+    @Published var editingNickname = ""
+    @Published private(set) var pendingAvatarData: Data?
+    @Published private(set) var pendingAvatarFileName: String?
+    @Published private(set) var avatarUploadProgress: Int?
 
     var displayNickname: String {
         nonEmpty(userInfo?.nickname) ?? "未设置昵称"