Introduced a UserSessionFlowCoordinator and split up the AppCoordinator state machine (#212)

ElementX/Sources/Application/AppDelegate.swift

@@ -0,0 +1,39 @@
+//
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import UIKit
+
+@main
+class AppDelegate: UIResponder, UIApplicationDelegate {
+    private lazy var appCoordinator: Coordinator = Tests.isRunningUITests ? UITestsAppCoordinator() : AppCoordinator()
+
+    func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
+        //  use `en` as fallback language
+        Bundle.elementFallbackLanguage = "en"
+
+        return true
+    }
+    
+    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
+        if Tests.isRunningUnitTests {
+            return true
+        }
+        
+        appCoordinator.start()
+        
+        return true
+    }
+}