Add countdown animation before game starts

Currently, when the player clicks Play Game the game starts instantly. This can catch users off guard, especially new players.

Suggested Enhancement:

Show a countdown: Ready..Set... Go! before starting the ball movement.

The countdown should appear centered on the game canvas or screen.

After the countdown, start the game loop as usual.

BENEFITS:

Improves user experience and readiness.

Adds a more polished, game-like feel.