refactor(project): use unified utcnow

app/database/password_reset.py

@@ -4,7 +4,9 @@
 
 from __future__ import annotations
 
-from datetime import UTC, datetime
+from datetime import datetime
+
+from app.utils import utcnow
 
 from sqlalchemy import BigInteger, Column, ForeignKey
 from sqlmodel import Field, SQLModel
@@ -19,7 +21,7 @@ class PasswordReset(SQLModel, table=True):
     user_id: int = Field(sa_column=Column(BigInteger, ForeignKey("lazer_users.id"), nullable=False, index=True))
     email: str = Field(index=True)
     reset_code: str = Field(max_length=8)  # 8位重置验证码
-    created_at: datetime = Field(default_factory=lambda: datetime.now(UTC))
+    created_at: datetime = Field(default_factory=utcnow)
     expires_at: datetime = Field()  # 验证码过期时间
     is_used: bool = Field(default=False)  # 是否已使用
     used_at: datetime | None = Field(default=None)