feat: add complete Mayday iOS Xcode project

- Swift 6, SwiftUI, MVVM + async/await architecture
- iOS 17.0 minimum deployment target
- Two targets: Mayday app + MaydayLiveActivity widget extension
- Models: UserResponse, TokenPair, AppNotification, SessionResponse, AlertAttributes
- Services: HTTPClient (actor), AuthService, KeychainService, NotificationsAPIService, PushNotificationService
- ViewModels: AuthViewModel, NotificationsViewModel, SettingsViewModel
- Views: Login/Register/VerifyEmail, NotificationsList/Detail, Settings/ChangePassword/Sessions
- APNs push notifications with UIApplicationDelegate
- ActivityKit Live Activities for Dynamic Island + Lock Screen
- Keychain (Security framework) token storage
- 30-second polling with pagination for notifications
- Xcode project file (project.pbxproj) with correct build phases for both targets

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Mayday/Models/User.swift

@@ -0,0 +1,61 @@
+import Foundation
+
+struct UserResponse: Codable, Identifiable {
+    let id: UUID
+    let email: String
+    let status: UserStatus
+    let metadata: [String: AnyCodable]?
+    let emailVerifiedAt: Date?
+    let roles: [String]
+    let createdAt: Date
+    let updatedAt: Date
+
+    enum CodingKeys: String, CodingKey {
+        case id, email, status, metadata, roles
+        case emailVerifiedAt = "email_verified_at"
+        case createdAt = "created_at"
+        case updatedAt = "updated_at"
+    }
+}
+
+enum UserStatus: String, Codable {
+    case pending
+    case active
+    case suspended
+    case deleted
+}
+
+// Helper for Any JSON values
+struct AnyCodable: Codable {
+    let value: Any
+
+    init(_ value: Any) {
+        self.value = value
+    }
+
+    init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        if let int = try? container.decode(Int.self) {
+            value = int
+        } else if let double = try? container.decode(Double.self) {
+            value = double
+        } else if let bool = try? container.decode(Bool.self) {
+            value = bool
+        } else if let string = try? container.decode(String.self) {
+            value = string
+        } else {
+            value = ""
+        }
+    }
+
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        switch value {
+        case let int as Int: try container.encode(int)
+        case let double as Double: try container.encode(double)
+        case let bool as Bool: try container.encode(bool)
+        case let string as String: try container.encode(string)
+        default: try container.encode("")
+        }
+    }
+}