refactor(dependencies): remove unused CountryService

- Remove import statement for CountryService
- Remove CountryService initialization in AppDependencies class
- Remove related repositories from dependencies initialization

Author: fulleni

lib/src/config/app_dependencies.dart

@@ -9,7 +9,6 @@ import 'package:flutter_news_app_api_server_full_source_code/src/config/environm
 import 'package:flutter_news_app_api_server_full_source_code/src/rbac/permission_service.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/services/auth_service.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/services/auth_token_service.dart';
-import 'package:flutter_news_app_api_server_full_source_code/src/services/country_service.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/services/dashboard_summary_service.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/services/database_seeding_service.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/services/default_user_preference_limit_service.dart';
@@ -62,7 +61,6 @@ class AppDependencies {
   late final EmailRepository emailRepository;
 
   // Services
-  late final CountryService countryService;
   late final TokenBlacklistService tokenBlacklistService;
   late final AuthTokenService authTokenService;
   late final VerificationCodeStorageService verificationCodeStorageService;
@@ -239,12 +237,6 @@ class AppDependencies {
         connectionManager: _mongoDbConnectionManager,
         log: Logger('MongoDbRateLimitService'),
       );
-      countryService = CountryService(
-        countryRepository: countryRepository,
-        headlineRepository: headlineRepository,
-        sourceRepository: sourceRepository,
-        logger: Logger('CountryService'),
-      );
 
       _isInitialized = true;
       _log.info('Application dependencies initialized successfully.');