Refactor tenders pagination and enhance API integration

- Updated TendersRepository and TendersService to support cursor-based pagination.
- Modified TendersViewModel to manage pagination state and handle API responses more effectively.
- Replaced existing pagination UI components with a new WindowedPagination widget across desktop, mobile, and tablet views.
- Improved notification handling in the UI to reflect the presence of notifications dynamically.
- Adjusted main tenders slider to ensure proper rendering based on the current page index.

lib/data/services/model/meta/meta.dart

@@ -13,6 +13,9 @@ abstract class Meta with _$Meta {
     required int? page,
     required int? pages,
     required int? total,
+    @JsonKey(name: 'has_more') bool? hasMore,
+    @JsonKey(name: 'next_cursor') String? nextCursor,
+    @JsonKey(name: 'prev_cursor') String? prevCursor,
   }) = _Meta;
 
   factory Meta.fromJson(Map<String, dynamic> json) => _$MetaFromJson(json);