Add unit tests for models and services

- Implemented unit tests for Object model including folder and file creation, properties, and path retrieval.
- Added unit tests for Setting model covering creation, unique constraints, and type enumeration.
- Created unit tests for User model focusing on user creation, uniqueness, and group relationships.
- Developed unit tests for Login service to validate login functionality, including 2FA and token generation.
- Added utility tests for JWT creation and verification, ensuring token integrity and expiration handling.
- Implemented password utility tests for password generation, hashing, and TOTP verification.

tests/fixtures/__init__.py

@@ -0,0 +1,14 @@
+"""
+测试数据工厂模块
+
+提供便捷的测试数据创建工具，用于在测试中快速生成用户、用户组、对象等数据。
+"""
+from .users import UserFactory
+from .groups import GroupFactory
+from .objects import ObjectFactory
+
+__all__ = [
+    "UserFactory",
+    "GroupFactory",
+    "ObjectFactory",
+]