* Add missing Telegram WebApp API classes and fields (#1424)
* Implemented `WebAppChat` class with fields `id`, `type`, `title`, `username`, and `photo_url` as per Telegram documentation.
* Modified `WebAppUser` class by adding `is_premium`, `added_to_attachment_menu`, and `allows_write_to_pm` fields.
* Modified `WebAppInitData` class to include `chat`, `chat_type`, `chat_instance` fields for full API support.
* fix changelog file name
* fix line too long
