refactor(app): reorganize splash screen remover files and update imports

- Move splash_remover_stub.dart, splash_remover_web.dart, and web_splash.dart into a new splash_screen_remover directory
- Rename web_splash.dart to web_splash_remover.dart for consistency
- Update import statement in main.dart to reflect the new file structure

Author: fulleni

lib/app/services/splash_remover_stub.dart …_screen_remover/splash_remover_stub.dartlib/app/services/splash_remover_stub.dart renamed to lib/app/services/splash_screen_remover/splash_remover_stub.dart lib/app/services/splash_remover_stub.dart renamed to lib/app/services/splash_screen_remover/splash_remover_stub.dart

@@ -1,5 +1,5 @@
 import 'package:device_preview/device_preview.dart';
-import 'package:flutter_news_app_mobile_client_full_source_code/app/services/web_splash.dart';
+import 'package:flutter_news_app_mobile_client_full_source_code/app/services/splash_screen_remover/web_splash_remover.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_news_app_mobile_client_full_source_code/app/config/config.dart';