fix: remove Future.delayed to eliminate page transition flicker

lib/features/announcement/announcement_detail_page.dart

@@ -8,7 +8,6 @@ import '../../shared/widgets/form_field_row.dart';
 import 'announcement_model.dart';
 
 final announcementDetailProvider = FutureProvider.autoDispose.family<AnnouncementModel, String>((ref, id) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return AnnouncementModel(
     id: id,
     title: '关于2026年端午节放假安排的通知',

lib/features/announcement/announcement_list_controller.dart

@@ -50,6 +50,5 @@ final _mockAnnouncements = <AnnouncementModel>[
 final announcementListProvider =
     FutureProvider.autoDispose.family<List<AnnouncementModel>, int>(
         (ref, page) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return _mockAnnouncements;
 });

lib/features/expense/expense_detail_page.dart

@@ -12,7 +12,6 @@ import 'expense_model.dart';
 final expenseDetailProvider =
     FutureProvider.autoDispose.family<ExpenseModel, String>(
         (ref, id) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return ExpenseModel(
     id: id,
     reportNo: 'BX202605001',

lib/features/expense/expense_list_controller.dart

@@ -158,7 +158,6 @@ final _mockExpenses = <ExpenseModel>[
 final expenseListProvider =
     FutureProvider.autoDispose.family<List<ExpenseModel>, int>(
         (ref, page) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   final status = ref.watch(expenseStatusFilterProvider);
   if (status.isEmpty) {
     return _mockExpenses;

lib/features/home/home_controller.dart

@@ -23,7 +23,6 @@ class HomeSummary {
 }
 
 final homeSummaryProvider = FutureProvider<HomeSummary>((ref) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return const HomeSummary(
     expensePending: 3,
     overtimePending: 1,

lib/features/outing_log/outing_log_detail_page.dart

@@ -8,7 +8,6 @@ import '../../shared/widgets/form_field_row.dart';
 import 'outing_log_model.dart';
 
 final outingLogDetailProvider = FutureProvider.autoDispose.family<OutingLogModel, String>((ref, id) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return OutingLogModel(
     id: id,
     visitNo: 'VL202605001',

lib/features/outing_log/outing_log_list_controller.dart

@@ -53,6 +53,5 @@ final _mockLogs = <OutingLogModel>[
 final outingLogListProvider =
     FutureProvider.autoDispose.family<List<OutingLogModel>, int>(
         (ref, page) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return _mockLogs;
 });

lib/features/overtime/overtime_detail_page.dart

@@ -10,7 +10,6 @@ import '../../shared/widgets/status_tag.dart';
 import 'overtime_model.dart';
 
 final overtimeDetailProvider = FutureProvider.autoDispose.family<OvertimeModel, String>((ref, id) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return OvertimeModel(
     id: id,
     applicationNo: 'OT202605001',

lib/features/overtime/overtime_list_controller.dart

@@ -103,7 +103,6 @@ final _mockOvertimes = <OvertimeModel>[
 final overtimeListProvider =
     FutureProvider.autoDispose.family<List<OvertimeModel>, int>(
         (ref, page) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   final status = ref.watch(overtimeStatusFilterProvider);
   if (status.isEmpty) {
     return _mockOvertimes;

lib/features/vehicle/vehicle_detail_page.dart

@@ -10,7 +10,6 @@ import '../../shared/widgets/status_tag.dart';
 import 'vehicle_model.dart';
 
 final vehicleDetailProvider = FutureProvider.autoDispose.family<VehicleModel, String>((ref, id) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   return VehicleModel(
     id: id,
     applicationNo: 'VH202605001',

lib/features/vehicle/vehicle_list_controller.dart

@@ -82,7 +82,6 @@ final _mockVehicles = <VehicleModel>[
 final vehicleListProvider =
     FutureProvider.autoDispose.family<List<VehicleModel>, int>(
         (ref, page) async {
-  await Future.delayed(const Duration(milliseconds: 300));
   final status = ref.watch(vehicleStatusFilterProvider);
   if (status.isEmpty) {
     return _mockVehicles;