fix: Correct parameter order in high score recording

Fixed the order of parameters passed to add_score() method to match
the expected signature (wpm, accuracy, difficulty) instead of
(difficulty, wpm, accuracy).

src/gui.py

@@ -207,9 +207,9 @@ def end_test(self) -> None:
 
         results = self.game.calculate_results(self.input_field.get())
         self.high_scores.add_score(
-            self.game.difficulty,
             results['wpm'],
-            results['accuracy']
+            results['accuracy'],
+            self.game.difficulty
         )
 
         self.input_field.configure(state='disabled')