All issues solved & Refactored

[Krishnnavadiya]

This PR implements the following improvements and fixes for the Snake Game:

• Added functionality to maintain and update the score dynamically as the game progresses.
• Implemented feature to track and display the top 10 highest scores.
• Introduced poisonous food items that the snake must avoid.
• Fixed bug where food could spawn inside the snake's body.
• Added play/pause functionality to improve user control.
• Increased game difficulty level gradually to enhance gameplay challenge.

[Krishnnavadiya]

• Improved code structure and consistency across snake.h, main.cpp, and snake_test.cpp
• Standardized naming conventions for better clarity
• Simplified readability without changing core logic or functionality