feat(headlines-feed): add sorting options for countries fetching

- Add descending sort by 'name' when fetching all countries
- Add descending sort by 'updatedAt' when fetching more countries

Author: fulleni

lib/headlines-feed/bloc/countries_filter_bloc.dart

@@ -53,6 +53,7 @@ class CountriesFilterBloc
     try {
       final response = await _countriesRepository.readAll(
         pagination: const PaginationOptions(limit: _countriesLimit),
+        sort: [const SortOption('name', SortOrder.desc)],
       );
       emit(
         state.copyWith(
@@ -85,6 +86,7 @@ class CountriesFilterBloc
           limit: _countriesLimit,
           cursor: state.cursor,
         ),
+        sort: [const SortOption('updatedAt', SortOrder.desc)],
       );
       emit(
         state.copyWith(