feat: authorize iOS Hermes accounts and secure session isolation

Sources/App/VoiceApp.swift

@@ -6,12 +6,12 @@ struct VoiceApp: App {
     @StateObject private var settings = SettingsStore()
 
     init() {
-        LiveKitSDK.setLogLevel(.debug)
+        LiveKitSDK.setLogLevel(.error)
     }
 
     var body: some Scene {
         WindowGroup {
-            ConversationView(settings: settings)
+            AuthenticationRoot(settings: settings)
                 .tint(Nearlight.rosewood)
         }
     }