fix(app): say it out loud when wake-ups do not work

Registration failures from the distributor were swallowed, so push looked
enabled while nothing arrived. Without wake-ups Android suspends the app
and messages only show up once the user opens it — which looks like broken
delivery even though the relay has them queued.

The failure is now remembered and surfaced in Settings, and the chat list
carries a dismissible line explaining the state.

app/lib/l10n/generated/app_localizations_en.dart

@@ -959,6 +959,18 @@ class AppLocalizationsEn extends AppLocalizations {
     return 'Setting up push failed: $error';
   }
 
+  @override
+  String get pushHintOff =>
+      'Messages arrive only when you open Šepot — wake-ups aren’t set up.';
+
+  @override
+  String get pushHintFailed =>
+      'Wake-ups aren’t working; you’ll see messages only after opening Šepot.';
+
+  @override
+  String get pushRegistrationFailed =>
+      'Wake-ups aren’t arriving — the distributor refused registration. Try turning push off and on again.';
+
   @override
   String get pushNoDistributorTitle => 'No distributor';