Add middleware and refactor admin handlers for improved functionality

- Introduced `DependenciesMiddleware` and `BlacklistMiddleware` for enhanced request handling across all routers.
- Refactored admin handlers to utilize new middleware, improving access control and error handling.
- Updated the `admin_router` to include middleware for access checks and streamlined the process of banning users.
- Enhanced the structure of admin handler imports for better organization and maintainability.
- Improved error handling in various admin functions to ensure robust user interactions.

helper_bot/handlers/admin/__init__.py

@@ -1 +1,37 @@
-from .admin_handlers import admin_router
+from .admin_handlers import admin_router
+from .dependencies import AdminAccessMiddleware, BotDB, Settings
+from .services import AdminService, User, BannedUser
+from .exceptions import (
+    AdminError, 
+    AdminAccessDeniedError, 
+    UserNotFoundError, 
+    InvalidInputError, 
+    UserAlreadyBannedError
+)
+from .utils import (
+    return_to_admin_menu, 
+    handle_admin_error, 
+    format_user_info, 
+    format_ban_confirmation,
+    escape_html
+)
+
+__all__ = [
+    'admin_router',
+    'AdminAccessMiddleware',
+    'BotDB',
+    'Settings',
+    'AdminService',
+    'User',
+    'BannedUser',
+    'AdminError',
+    'AdminAccessDeniedError',
+    'UserNotFoundError',
+    'InvalidInputError',
+    'UserAlreadyBannedError',
+    'return_to_admin_menu',
+    'handle_admin_error',
+    'format_user_info',
+    'format_ban_confirmation',
+    'escape_html'
+]