docs(game): update docstrings

src/py2048/screens/game.py

@@ -31,6 +31,7 @@ class Game:
                 self.move_down()
 
     def move(self, direction: Direction) -> None:
+        """Moved the board in the given direction and updates the score."""
         self.board.move(direction)
         self.header.update(self.board.score)
 

src/py2048/screens/header.py

@@ -42,9 +42,8 @@ class Header:
         return pygame.sprite.Group(self.score, highscore)
 
     def draw(self, surface: pygame.Surface) -> None:
-        """Draw the header."""
         self.labels.draw(surface)
 
-    def update(self, score: int) -> None:
-        """Update the score."""
-        self.score.update_score(score)
+    def update(self, new_score: int) -> None:
+        """Updates the score to `new_score`."""
+        self.score.update_score(new_score)