Highscore feature.

Add feature to save the high scores of the users.

The issue mentions adding a high score feature but provides no details. First, examine the existing game code to understand the current score tracking and game state. Look for any existing data persistence or storage mechanisms. Determine where user scores are calculated and how they could be saved (e.g., localStorage, a backend). The goal is to design and implement a way to store and display top scores.

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