Add comprehensive unit tests for iOS and Android/KMM

This commit adds extensive unit test coverage for the entire application,
including iOS ViewModels, design system, and shared Kotlin Multiplatform code.

iOS Unit Tests (49 tests):
- LoginViewModelTests: Authentication state and validation tests
- ResidenceViewModelTests: Residence loading and state management
- TaskViewModelTests: Task operations (cancel, archive, mark progress)
- DocumentViewModelTests: Document/warranty CRUD operations
- ContractorViewModelTests: Contractor management and favorites
- DesignSystemTests: Color system, typography, spacing, radius, shadows

Shared KMM Unit Tests (26 tests):
- AuthViewModelTest: Login, register, verify email state initialization
- TaskViewModelTest: Task state management verification
- DocumentViewModelTest: Document state initialization tests
- ResidenceViewModelTest: Residence state management tests
- ContractorViewModelTest: Contractor state initialization tests

Test Infrastructure:
- Reorganized test files from iosAppUITests to MyCribTests
- All shared KMM tests passing successfully (./gradlew test)
- Tests focus on state initialization and core functionality
- Ready for CI/CD integration

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

iosApp/MyCribTests/TestHelpers.swift

@@ -0,0 +1,180 @@
+import XCTest
+
+/// Helper extensions and utilities for UI tests
+extension XCUIApplication {
+    /// Launch the app and reset to initial state
+    func launchAndReset() {
+        launchArguments = ["--uitesting"]
+        launch()
+    }
+
+    /// Clear all text from a text field
+    func clearText(in textField: XCUIElement) {
+        textField.tap()
+        textField.press(forDuration: 1.2)
+        menuItems["Select All"].tap()
+        textField.typeText(XCUIKeyboardKey.delete.rawValue)
+    }
+}
+
+/// Base test class with common setup and teardown
+class BaseUITest: XCTestCase {
+    var app: XCUIApplication!
+
+    override func setUp() {
+        super.setUp()
+        continueAfterFailure = false
+        app = XCUIApplication()
+        app.launchAndReset()
+    }
+
+    override func tearDown() {
+        app = nil
+        super.tearDown()
+    }
+
+    // MARK: - Authentication Helpers
+
+    func login(username: String, password: String) {
+        let usernameField = app.textFields["Username"]
+        let passwordField = app.secureTextFields["Password"]
+        let loginButton = app.buttons["Login"]
+
+        if usernameField.exists {
+            usernameField.tap()
+            usernameField.typeText(username)
+        }
+
+        if passwordField.exists {
+            passwordField.tap()
+            passwordField.typeText(password)
+        }
+
+        if loginButton.exists {
+            loginButton.tap()
+        }
+    }
+
+    func logout() {
+        let profileTab = app.tabBars.buttons["Profile"]
+        profileTab.tap()
+
+        let logoutButton = app.buttons["Log Out"]
+        XCTAssertTrue(logoutButton.waitForExistence(timeout: 5))
+        logoutButton.tap()
+    }
+
+    func register(username: String, email: String, password: String, firstName: String = "", lastName: String = "") {
+        let signUpButton = app.buttons["Sign Up"]
+        XCTAssertTrue(signUpButton.waitForExistence(timeout: 3))
+        signUpButton.tap()
+
+        let usernameField = app.textFields["Username"]
+        let emailField = app.textFields["Email"]
+        let passwordField = app.secureTextFields["Password"]
+        let registerButton = app.buttons["Register"]
+
+        usernameField.tap()
+        usernameField.typeText(username)
+
+        emailField.tap()
+        emailField.typeText(email)
+
+        passwordField.tap()
+        passwordField.typeText(password)
+
+        if !firstName.isEmpty {
+            let firstNameField = app.textFields["First Name"]
+            firstNameField.tap()
+            firstNameField.typeText(firstName)
+        }
+
+        if !lastName.isEmpty {
+            let lastNameField = app.textFields["Last Name"]
+            lastNameField.tap()
+            lastNameField.typeText(lastName)
+        }
+
+        registerButton.tap()
+    }
+
+    // MARK: - Navigation Helpers
+
+    func navigateToTab(_ tabName: String) {
+        let tab = app.tabBars.buttons[tabName]
+        XCTAssertTrue(tab.waitForExistence(timeout: 3))
+        tab.tap()
+    }
+
+    func navigateBack() {
+        app.navigationBars.buttons.element(boundBy: 0).tap()
+    }
+
+    // MARK: - Assertion Helpers
+
+    func assertElementExists(_ identifier: String, timeout: TimeInterval = 5) {
+        let element = app.descendants(matching: .any).matching(identifier: identifier).firstMatch
+        XCTAssertTrue(element.waitForExistence(timeout: timeout), "Element '\(identifier)' does not exist")
+    }
+
+    func assertElementDoesNotExist(_ identifier: String, timeout: TimeInterval = 2) {
+        let element = app.descendants(matching: .any).matching(identifier: identifier).firstMatch
+        XCTAssertFalse(element.waitForExistence(timeout: timeout), "Element '\(identifier)' should not exist")
+    }
+
+    func assertNavigatedTo(title: String, timeout: TimeInterval = 5) {
+        let navigationBar = app.navigationBars[title]
+        XCTAssertTrue(navigationBar.waitForExistence(timeout: timeout), "Did not navigate to '\(title)'")
+    }
+
+    // MARK: - Wait Helpers
+
+    func wait(seconds: TimeInterval) {
+        Thread.sleep(forTimeInterval: seconds)
+    }
+
+    func waitForElementToAppear(_ element: XCUIElement, timeout: TimeInterval = 5) -> Bool {
+        return element.waitForExistence(timeout: timeout)
+    }
+
+    func waitForElementToDisappear(_ element: XCUIElement, timeout: TimeInterval = 5) -> Bool {
+        let predicate = NSPredicate(format: "exists == false")
+        let expectation = XCTNSPredicateExpectation(predicate: predicate, object: element)
+        let result = XCTWaiter.wait(for: [expectation], timeout: timeout)
+        return result == .completed
+    }
+}
+
+/// Identifiers for UI elements (for better testability)
+struct Identifiers {
+    struct Authentication {
+        static let usernameField = "UsernameField"
+        static let passwordField = "PasswordField"
+        static let loginButton = "LoginButton"
+        static let registerButton = "RegisterButton"
+        static let logoutButton = "LogoutButton"
+    }
+
+    struct Residence {
+        static let addButton = "AddResidenceButton"
+        static let editButton = "EditResidenceButton"
+        static let deleteButton = "DeleteResidenceButton"
+        static let nameField = "ResidenceNameField"
+        static let addressField = "ResidenceAddressField"
+    }
+
+    struct Task {
+        static let addButton = "AddTaskButton"
+        static let completeButton = "CompleteTaskButton"
+        static let editButton = "EditTaskButton"
+        static let titleField = "TaskTitleField"
+        static let descriptionField = "TaskDescriptionField"
+    }
+
+    struct MultiUser {
+        static let manageUsersButton = "ManageUsersButton"
+        static let generateCodeButton = "GenerateCodeButton"
+        static let joinButton = "JoinResidenceButton"
+        static let shareCodeField = "ShareCodeField"
+    }
+}