fix: improve plugin installation scope checks for verification

api/services/plugin/plugin_service.py

@@ -105,16 +105,19 @@ class PluginService:
     @staticmethod
     def _check_plugin_installation_scope(plugin_verification: Optional[PluginVerification]):
         """
-        Check the verification of the plugin
+        Check the plugin installation scope
         """
         features = FeatureService.get_system_features()
 
         match features.plugin_installation_permission.plugin_installation_scope:
             case PluginInstallationScope.OFFICIAL_ONLY:
-                if plugin_verification.authorized_category != PluginVerification.AuthorizedCategory.Langgenius:
+                if (
+                    plugin_verification is None
+                    or plugin_verification.authorized_category != PluginVerification.AuthorizedCategory.Langgenius
+                ):
                     raise PluginInstallationForbiddenError("Plugin installation is restricted to official only")
             case PluginInstallationScope.OFFICIAL_AND_SPECIFIC_PARTNERS:
-                if plugin_verification.authorized_category not in [
+                if plugin_verification is None or plugin_verification.authorized_category not in [
                     PluginVerification.AuthorizedCategory.Langgenius,
                     PluginVerification.AuthorizedCategory.Partner,
                 ]: