补充 Auth/Tasks/ScenicPermission/Live 单元测试，并完善 UI Test 登录与会话稳定性。

移除 LoginViewModel 硬编码账号，扩展登录流程测试覆盖；调整 ZLoginSmokeUITests 执行顺序与路由直达逻辑，避免清空 Keychain 影响其它用例。

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

suixinkan/Features/Auth/ViewModels/LoginViewModel.swift

@@ -70,8 +70,8 @@ enum LoginFlowError: LocalizedError {
 @MainActor
 /// 登录页 ViewModel，负责表单状态、登录请求和多账号选择流程。
 final class LoginViewModel: ObservableObject {
-    @Published var username = "18651857230"
-    @Published var password = "zhifly666"
+    @Published var username = ""
+    @Published var password = ""
     @Published var privacyChecked = false
     @Published var isLoading = false
     @Published var isSelectingAccount = false