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/callback/constants.py

@@ -0,0 +1,29 @@
+# Callback data constants
+CALLBACK_PUBLISH = "publish"
+CALLBACK_DECLINE = "decline"
+CALLBACK_BAN = "ban"
+CALLBACK_UNLOCK = "unlock"
+CALLBACK_RETURN = "return"
+CALLBACK_PAGE = "page"
+
+# Content types
+CONTENT_TYPE_TEXT = "text"
+CONTENT_TYPE_PHOTO = "photo"
+CONTENT_TYPE_VIDEO = "video"
+CONTENT_TYPE_VIDEO_NOTE = "video_note"
+CONTENT_TYPE_AUDIO = "audio"
+CONTENT_TYPE_VOICE = "voice"
+CONTENT_TYPE_MEDIA_GROUP = "^"
+
+# Messages
+MESSAGE_PUBLISHED = "Выложено!"
+MESSAGE_DECLINED = "Отклонено!"
+MESSAGE_USER_BANNED = "Пользователь заблокирован!"
+MESSAGE_USER_UNLOCKED = "Пользователь разблокирован"
+MESSAGE_ERROR = "Что-то пошло не так!"
+MESSAGE_POST_PUBLISHED = "Твой пост был выложен🥰"
+MESSAGE_POST_DECLINED = "Твой пост был отклонен😔"
+MESSAGE_USER_BANNED_SPAM = "Ты заблокирован за спам. Дата разблокировки: {date}"
+
+# Error messages
+ERROR_BOT_BLOCKED = "Forbidden: bot was blocked by the user"