Add iOS launch screen and app icon assets

- Created new app icon images for various sizes and added them to the asset catalog.
- Added launch images for different resolutions (1x, 2x, 3x) in the asset catalog.
- Updated the LaunchScreen storyboard to use the new launch images.
- Created a README for the launch image assets directory.
- Updated Info.plist to reference the new launch storyboard.
- Added a bridging header for Swift compatibility.
- Created initial test file for Runner application.
- Initialized project structure with necessary files and configurations.

ios/Runner/AppDelegate.swift

@@ -0,0 +1,13 @@
+import Flutter
+import UIKit
+
+@main
+@objc class AppDelegate: FlutterAppDelegate {
+  override func application(
+    _ application: UIApplication,
+    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
+  ) -> Bool {
+    GeneratedPluginRegistrant.register(with: self)
+    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
+  }
+}