- Updated the language configuration to use a single source of truth from `DEFAULT_LANGUAGE` for the bot, API, and Mini App, eliminating auto-detection from user settings.
- Refactored the `get_lang` function to always return `DEFAULT_LANGUAGE`, ensuring consistent language usage throughout the application.
- Modified the handling of language in various components, including API responses and UI elements, to reflect the new language management approach.
- Enhanced documentation and comments to clarify the changes in language handling.
- Added unit tests to verify the new language handling behavior and ensure coverage for the updated functionality.
- Deleted the `app.js` file and migrated its functionality to a modular structure with multiple JavaScript files for better organization and maintainability.
- Updated `index.html` to reference the new `main.js` module, ensuring proper loading of the application.
- Introduced new utility modules for API requests, authentication, calendar handling, and DOM manipulation to enhance code clarity and separation of concerns.
- Enhanced CSS styles for improved layout and theming consistency across the application.
- Added comprehensive comments and documentation to new modules to facilitate future development and understanding.
