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>

suixinkanUITests/Auth/ZLoginSmokeUITests.swift

@@ -0,0 +1,71 @@
+//
+//  ZLoginSmokeUITests.swift
+//  suixinkanUITests
+//
+//  命名以 Z 开头，确保在全套件末尾执行，避免清空 Keychain 影响其它用例。
+//
+
+import XCTest
+
+final class ZLoginSmokeUITests: XCTestCase {
+    override func setUp() {
+        super.setUp()
+        continueAfterFailure = false
+        UITestSession.invalidate()
+    }
+
+    override func tearDown() {
+        UITestSession.invalidate()
+        super.tearDown()
+    }
+
+    /// 测试冷启动会展示登录页关键控件。
+    func testFreshLaunchShowsLoginScreen() {
+        let app = SuixinkanApp(resetState: true).launch(waitForLoading: false)
+
+        XCTAssertTrue(app.application.staticTexts["login.title"].waitForExistence(timeout: 8))
+        XCTAssertTrue(app.application.textFields["login.username"].exists)
+        XCTAssertTrue(
+            app.application.secureTextFields["login.password"].exists
+                || app.application.textFields["login.password"].exists
+        )
+        XCTAssertTrue(app.application.buttons["login.submit"].exists)
+        XCTAssertTrue(app.application.buttons["login.userAgreement"].exists)
+        XCTAssertTrue(app.application.buttons["login.privacyPolicy"].exists)
+        app.application.terminate()
+    }
+
+    /// 测试未勾选协议时无法直接登录。
+    func testLoginRequiresPrivacyAgreement() throws {
+        let app = SuixinkanApp(resetState: true).launch(waitForLoading: false)
+        defer { app.application.terminate() }
+        guard UITestLaunchConfiguration.credentials != nil else {
+            throw XCTSkip("缺少 UI Test 账号。")
+        }
+
+        let usernameField = app.application.textFields["login.username"]
+        XCTAssertTrue(usernameField.waitForExistence(timeout: 8))
+        XCTAssertFalse(app.application.buttons["login.submit"].isEnabled)
+    }
+
+    /// 测试空密码不会离开登录页。
+    func testEmptyPasswordDoesNotLeaveLoginScreen() throws {
+        let app = SuixinkanApp(resetState: true).launch(waitForLoading: false)
+        defer { app.application.terminate() }
+        let credentials = try UITestLaunchConfiguration.requireCredentials()
+
+        let usernameField = app.application.textFields["login.username"]
+        XCTAssertTrue(usernameField.waitForExistence(timeout: 8))
+        usernameField.tap()
+        usernameField.typeText(credentials.phone)
+
+        let privacyToggle = app.application.buttons["login.privacy"]
+        if privacyToggle.exists {
+            privacyToggle.tap()
+        }
+
+        app.application.buttons["login.submit"].tap()
+        app.waitForGlobalLoadingToDisappear(timeout: 5)
+        XCTAssertTrue(app.isOnLoginScreen)
+    }
+}