drawDead method
Implementation
void drawDead(Direction dir) {
final ahead = Point(
head.x +
(dir == Direction.right
? 1
: dir == Direction.left
? -1
: 0),
head.y +
(dir == Direction.down
? 1
: dir == Direction.up
? -1
: 0));
drawChar(head, '💀');
drawChar(ahead, '💥');
}