loading state and error handling refactor

lib/view/pages/talk/chat_list.dart

@@ -12,6 +12,7 @@ import '../../../state/app/modules/chatList/bloc/chat_list_state.dart';
 import '../../../notification/notify_updater.dart';
 import '../../../state/app/modules/settings/bloc/settings_cubit.dart';
 import '../../../widget/confirm_dialog.dart';
+import '../../../widget/placeholder_view.dart';
 import 'widgets/chat_tile.dart';
 import 'widgets/split_view_placeholder.dart';
 import 'join_chat.dart';
@@ -144,9 +145,7 @@ class _ChatListViewState extends State<_ChatListView> {
                   title: 'Chat starten',
                   content: "Möchtest du einen Chat mit Nutzer '$username' starten?",
                   confirmButton: 'Chat starten',
-                  onConfirm: () {
-                    bloc.createDirectChat(username);
-                  },
+                  onConfirmAsync: () => bloc.createDirectChat(username),
                 ).asDialog(context);
               });
             },
@@ -164,6 +163,13 @@ class _ChatListViewState extends State<_ChatListView> {
                 unreadToTop: talkSettings.sortUnreadToTop,
               );
 
+              if (sorted.isEmpty) {
+                return const PlaceholderView(
+                  icon: Icons.chat_bubble_outline,
+                  text: 'Noch keine Chats — starte einen über das +-Symbol.',
+                );
+              }
+
               return ListView(
                 padding: EdgeInsets.zero,
                 children: sorted.map((room) {