fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理
- 修复PEP8格式问题 (E302, E305, E501)
- 修复行长度超过100字符的问题
- 修复F821未定义名称错误

backend/api_key_manager.py

@@ -15,11 +15,13 @@ from enum import Enum
 
 DB_PATH = os.getenv("DB_PATH", "/app/data/insightflow.db")
 
+
 class ApiKeyStatus(Enum):
     ACTIVE = "active"
     REVOKED = "revoked"
     EXPIRED = "expired"
 
+
 @dataclass
 class ApiKey:
     id: str
@@ -37,6 +39,7 @@ class ApiKey:
     revoked_reason: str | None
     total_calls: int = 0
 
+
 class ApiKeyManager:
     """API Key 管理器"""
 
@@ -106,7 +109,8 @@ class ApiKeyManager:
                 CREATE INDEX IF NOT EXISTS idx_api_keys_owner ON api_keys(owner_id);
                 CREATE INDEX IF NOT EXISTS idx_api_logs_key_id ON api_call_logs(api_key_id);
                 CREATE INDEX IF NOT EXISTS idx_api_logs_created ON api_call_logs(created_at);
-                CREATE INDEX IF NOT EXISTS idx_api_stats_key_date ON api_call_stats(api_key_id, date);
+                CREATE INDEX IF NOT EXISTS idx_api_stats_key_date
+                ON api_call_stats(api_key_id, date);
             """)
             conn.commit()
 
@@ -522,9 +526,11 @@ class ApiKeyManager:
             total_calls=row["total_calls"],
         )
 
+
 # 全局实例
 _api_key_manager: ApiKeyManager | None = None
 
+
 def get_api_key_manager() -> ApiKeyManager:
     """获取 API Key 管理器实例"""
     global _api_key_manager