Initial scaffold — NASBackup iOS app

Full project scaffold: XcodeGen project.yml, Core models/protocols/errors,
SMBService (kishikawakatsumi/SMBClient), SFTPService (Citadel 0.9.2),
PhotoLibraryService, LANMonitor, BackupEngine, BackgroundTaskManager,
all feature UIs (Login, Connect, Browse, Backup, History, Settings),
Shared components and theme. Builds clean with zero errors.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

App/SceneDelegate.swift

@@ -0,0 +1,14 @@
+import UIKit
+import SwiftUI
+
+final class SceneDelegate: NSObject, UIWindowSceneDelegate {
+    var window: UIWindow?
+
+    func scene(
+        _ scene: UIScene,
+        willConnectTo session: UISceneSession,
+        options connectionOptions: UIScene.ConnectionOptions
+    ) {
+        // SwiftUI lifecycle handles window setup via NASBackupApp.swift
+    }
+}