Update dependencies, enhance API endpoints, and refactor UI components

- Updated `pubspec.lock` to new package versions for `async`, `fake_async`, `leak_tracker`, and `vm_service`.
- Modified API endpoint for unread notifications to include `event_type=PUSH`.
- Refactored `CompletionOfDocumentsMobilePage` layout for improved structure.
- Simplified `DetailDropDown` widget by removing unnecessary animations.
- Updated `CommentBox` styling and adjusted padding for better UI consistency.
- Replaced deprecated `FormCard` implementation in final completion pages with a new widget structure.
- Enhanced button styles across various dialogs and pages for a cohesive design.

lib/views/tenders/widgets/tenders_filter_dialog.dart

@@ -230,7 +230,7 @@ class _TendersFilterDialogState extends State<TendersFilterDialog> {
                     },
                     text: TendersStrings.confirm,
                     textColor: AppColors.textBlue,
-                    backgroundColor: AppColors.primary2,
+                    backgroundColor: AppColors.primary20,
                   ),
                 ),
               ],

lib/views/tenders/widgets/tenders_sort_dialog.dart

@@ -103,7 +103,7 @@ class _TendersSortDialogState extends State<TendersSortDialog> {
                     },
                     text: TendersStrings.confirm,
                     textColor: AppColors.textBlue,
-                    backgroundColor: AppColors.primary2,
+                    backgroundColor: AppColors.primary20,
                   ),
                 ),
               ],