* Refactor and improve bot messages
Refactored bot code to use aiogram enumerations and enhanced chat messages with markdown beautifications for a more user-friendly display.
CommandStart() is now used instead of Command('start') for readability.
Furthermore, the bot's 'stop' command was improved, ensuring it executes appropriately during KeyboardInterrupt or SystemExit.
Additionally, the bot's logging was adjusted to output to sys.stdout for better logs' readability.
* Added Changelog
* Add guidance comments on obtaining bot tokens from environment variables
* Remove hardcoded tokens, opt for environment variable
* Remove unnecessary spaces and reorganize imports
* Fix error, switch default storage from Redis to Memory, and add logging to multibot example
