replaced account data singleton with a session model

lib/state/app/infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart

@@ -5,7 +5,7 @@ import 'package:hydrated_bloc/hydrated_bloc.dart';
 
 import '../../../../../api/errors/error_mapper.dart';
 import '../../../../../api/errors/stale_session_exception.dart';
-import '../../../../../model/account_data.dart';
+import '../../../../../session/session_manager.dart';
 import '../../../../../utils/session_single_flight.dart';
 import '../../loadable_state/loadable_state.dart';
 import '../../loadable_state/loading_error.dart';
@@ -132,12 +132,12 @@ abstract class LoadableHydratedBloc<
   /// its async continuations, are dropped once the account signed out, so a
   /// late response of the previous account cannot refill the reset bloc.
   R runInSession<R>(R Function() body) =>
-      runZoned(body, zoneValues: {_sessionKey: AccountData().sessionEpoch});
+      runZoned(body, zoneValues: {_sessionKey: SessionManager().sessionEpoch});
 
   @override
   void add(LoadableHydratedBlocEvent<TState> event) {
     final epoch = Zone.current[_sessionKey];
-    if (epoch is int && !AccountData().isCurrentSession(epoch)) return;
+    if (epoch is int && !SessionManager().isCurrentSession(epoch)) return;
     super.add(event);
   }
 

lib/state/app/modules/capabilities/bloc/capabilities_cubit.dart

@@ -5,7 +5,7 @@ import 'package:hydrated_bloc/hydrated_bloc.dart';
 import '../../../../../api/demo/data/demo_capabilities.dart';
 import '../../../../../api/demo/demo_mode.dart';
 import '../../../../../api/marianumconnect/queries/get_capabilities/get_capabilities.dart';
-import '../../../../../model/account_data.dart';
+import '../../../../../session/session_manager.dart';
 import 'capabilities_state.dart';
 
 /// Holds the current user's mobile capability flags. Hydrated so the last
@@ -35,12 +35,12 @@ class CapabilitiesCubit extends HydratedCubit<CapabilitiesState> {
       emit(DemoCapabilities.state());
       return;
     }
-    final epoch = AccountData().sessionEpoch;
+    final epoch = SessionManager().sessionEpoch;
     try {
       final response = await GetCapabilities().run();
       // A slow answer for the previous account must not decide the modules
       // of the next one.
-      if (!AccountData().isCurrentSession(epoch)) return;
+      if (!SessionManager().isCurrentSession(epoch)) return;
       emit(
         CapabilitiesState(
           viewForeignTimetables: response.viewForeignTimetables,

lib/state/app/modules/nextcloud_capabilities/bloc/nextcloud_capabilities_cubit.dart

@@ -5,7 +5,7 @@ import 'package:hydrated_bloc/hydrated_bloc.dart';
 import '../../../../../api/demo/data/demo_capabilities.dart';
 import '../../../../../api/demo/demo_mode.dart';
 import '../../../../../api/marianumcloud/capabilities/get_nextcloud_capabilities.dart';
-import '../../../../../model/account_data.dart';
+import '../../../../../session/session_manager.dart';
 import 'nextcloud_capabilities_state.dart';
 
 /// Holds the current user's Nextcloud `files_sharing` capabilities. Hydrated so
@@ -60,16 +60,17 @@ class NextcloudCapabilitiesCubit
   /// Refreshes capabilities from the server. On any failure the previously
   /// hydrated flags are kept but the state is marked `loaded`.
   Future<void> load() async {
+    if (!SessionManager().hasNextcloud) return;
     if (DemoMode.active) {
       emit(DemoNextcloudCapabilities.state());
       return;
     }
-    final epoch = AccountData().sessionEpoch;
+    final epoch = SessionManager().sessionEpoch;
     try {
       final caps = await GetNextcloudCapabilities().run();
       // A slow answer for the previous account must not decide the modules
       // of the next one.
-      if (!AccountData().isCurrentSession(epoch)) return;
+      if (!SessionManager().isCurrentSession(epoch)) return;
       emit(
         NextcloudCapabilitiesState(
           apiEnabled: caps.apiEnabled,