fixed stale state after logout and replayed or lost share intents

lib/api/errors/stale_session_exception.dart

@@ -0,0 +1,11 @@
+import 'app_exception.dart';
+
+/// A request finished after the account it was started for signed out. Its
+/// result must not reach the state or cache of whoever is signed in now.
+class StaleSessionException extends AppException {
+  const StaleSessionException()
+    : super(
+        userMessage: 'Die Anmeldung hat sich geändert. Bitte lade neu.',
+        technicalDetails: 'result of a previous session discarded',
+      );
+}