Prepare onboarding flow for personalisation screens.

Add a BuildSetting to control the display of the personalisation screens.
Add a property to delay the AuthenticationCoordinator from showing any screens.
Add Congratulations screen to onboarding flow.

RiotSwiftUI/Modules/AnalyticsPrompt/View/AnalyticsPrompt.swift

@@ -125,6 +125,8 @@ struct AnalyticsPrompt: View {
             .background(theme.colors.background.ignoresSafeArea())
             .accentColor(theme.colors.accent)
         }
+        .navigationBarHidden(true)
+        .navigationBarBackButtonHidden(true)
     }
 }