Add xx-messenger example

...messenger/Sources/AppCore/DBManager/DBManagerMakeDB.swift

Examples/xx-messenger/Sources/AppFeature/App.swift

...xx-messenger/Sources/AppFeature/AppEnvironment+Live.swift

Examples/xx-messenger/Sources/AppFeature/AppFeature.swift

Examples/xx-messenger/Sources/AppFeature/AppView.swift

Examples/xx-messenger/Sources/HomeFeature/HomeFeature.swift

Examples/xx-messenger/Sources/HomeFeature/HomeView.swift

.../xx-messenger/Sources/LaunchFeature/LaunchErrorView.swift

...es/xx-messenger/Sources/LaunchFeature/LaunchFeature.swift

Examples/xx-messenger/Sources/LaunchFeature/LaunchView.swift

...x-messenger/Sources/RegisterFeature/RegisterFeature.swift

...s/xx-messenger/Sources/RegisterFeature/RegisterView.swift

.../xx-messenger/Sources/RestoreFeature/RestoreFeature.swift

...les/xx-messenger/Sources/RestoreFeature/RestoreView.swift

.../xx-messenger/Sources/WelcomeFeature/WelcomeFeature.swift

...les/xx-messenger/Sources/WelcomeFeature/WelcomeView.swift

Examples/xx-messenger/Tests/AppCoreTests/AppCoreTests.swift

.../xx-messenger/Tests/AppFeatureTests/AppFeatureTests.swift

...x-messenger/Tests/HomeFeatureTests/HomeFeatureTests.swift

...ssenger/Tests/LaunchFeatureTests/LaunchFeatureTests.swift