style: format all Python files with Black

Apply Black formatter to the entire codebase for consistent code style.

Co-Authored-By: Claude (glm-5) <noreply@anthropic.com>

auth/__init__.py

@@ -1,6 +1,7 @@
 """
 Auth package for user authentication and session management
 """
+
 from .session_manager import SessionManager
 
-__all__ = ['SessionManager']
+__all__ = ["SessionManager"]