feat(games): 게임 리셋 시, 방향벡터의 초기값을 특정 범위 내에서 할당

frontend/src/pages/local-game/page.js

@@ -370,8 +370,8 @@ export default function LocalGame($container, info = null) {
       ball.x = canvas.width / 2;
       ball.y = canvas.height / 2;
       ball.direction = {
-        x: Math.random() * 2 - 1,
-        y: Math.random() * 2 - 1,
+        x: (Math.random() * 2 - 1) * getRandomCoefficient(0.7, 0.9),
+        y: (Math.random() * 2 - 1) * getRandomCoefficient(0.7, 0.9),
       };
       normalizeVector(ball.direction.x, ball.direction.y);
       ball.speed = BALL_SPEED;