style: 代码格式化

src/heurams/kernel/puzzles/base.py

@@ -1,9 +1,9 @@
 # base.py
 class BasePuzzle:
     """谜题基类"""
-    
+
     def refresh(self):
         raise NotImplementedError("谜题对象未实现 refresh 方法")
-    
+
     def __str__(self):
-        return f"谜题: {type(self).__name__}"
+        return f"谜题: {type(self).__name__}"