feat(ads): pass ad theme style to headlines feed on initial load

- Import AdThemeStyle model
- Modify router to pass AdThemeStyle to HeadlinesFeedFetchRequested event
- Use Theme.of(context) to determine ad theme style

Author: fulleni

lib/router/router.dart

@@ -12,6 +12,7 @@ import 'package:flutter_news_app_mobile_client_full_source_code/account/view/man
 import 'package:flutter_news_app_mobile_client_full_source_code/account/view/manage_followed_items/topics/followed_topics_list_page.dart';
 import 'package:flutter_news_app_mobile_client_full_source_code/account/view/saved_headlines_page.dart';
 import 'package:flutter_news_app_mobile_client_full_source_code/ads/ad_service.dart';
+import 'package:flutter_news_app_mobile_client_full_source_code/ads/models/ad_theme_style.dart';
 import 'package:flutter_news_app_mobile_client_full_source_code/app/bloc/app_bloc.dart';
 import 'package:flutter_news_app_mobile_client_full_source_code/app/config/config.dart'
     as local_config;
@@ -371,7 +372,11 @@ GoRouter createRouter({
                         .read<DataRepository<UserContentPreferences>>(),
                     feedDecoratorService: feedDecoratorService,
                     appBloc: context.read<AppBloc>(),
-                  )..add(const HeadlinesFeedFetchRequested());
+                  )..add(
+                      HeadlinesFeedFetchRequested(
+                        adThemeStyle: AdThemeStyle.fromTheme(Theme.of(context)),
+                      ),
+                    );
                 },
               ),
               BlocProvider(