custom login implementation, period-based timetable layout with overlap handling, enhanced error dialogs, and unified bottom sheets

lib/view/pages/overhang.dart

@@ -127,7 +127,7 @@ class _OverhangState extends State<Overhang> {
                   },
                   onError: (error) {
                     if (!context.mounted) return;
-                    InfoDialog.show(context, error.toString());
+                    InfoDialog.show(context, error.toString(), copyable: true, title: 'Fehler');
                   },
                 );
               },