feat(filter-dialog): add reset filters functionality

- Add IconButton to reset filters in FilterDialog
- Implement logic to dispatch reset event and apply default filters
- Update UI to reflect reset state after reset action

Author: fulleni

lib/content_management/widgets/filter_dialog/filter_dialog.dart

@@ -112,6 +112,30 @@ class _FilterDialogState extends State<FilterDialog> {
               onPressed: () => Navigator.of(context).pop(),
             ),
             actions: [
+              IconButton(
+                icon: const Icon(Icons.refresh),
+                tooltip: l10n.resetFiltersButtonText,
+                onPressed: () {
+                  // Dispatch reset event
+                  context.read<FilterDialogBloc>().add(
+                        const FilterDialogReset(),
+                      );
+                  // After reset, get the new state and apply filters
+                  final resetState =
+                      context.read<FilterDialogBloc>().state.copyWith(
+                            searchQuery: '',
+                            selectedStatus: ContentStatus.active,
+                            selectedSourceIds: [],
+                            selectedTopicIds: [],
+                            selectedCountryIds: [],
+                            selectedSourceTypes: [],
+                            selectedLanguageCodes: [],
+                            selectedHeadquartersCountryIds: [],
+                          );
+                  _dispatchFilterApplied(resetState);
+                  Navigator.of(context).pop();
+                },
+              ),
               IconButton(
                 icon: const Icon(Icons.check),
                 tooltip: l10n.applyFilters,