feat: add log cleanup time setting to system settings

Author: wxg0103

apps/system_manage/models/system_setting.py

@@ -18,6 +18,8 @@ class SettingType(models.IntegerChoices):
 
     RSA = 1, "私钥秘钥"
 
+    LOG = 2, "日志清理时间"
+
 
 class SystemSetting(AppModelMixin):
     """