Round 5 fixes: workerpool resize shrink, validator lazy session close, plugin config error handling, 422 message detail, tests

app/services/plugin_service.py

@@ -82,10 +82,13 @@ class PluginService:
             raise PluginNotFoundException(plugin_id)
         safe_config = {k: v for k, v in config.items() if k in plugin.default_config}
         if not safe_config:
-            return False
+            raise ValidationException("配置项无效或为空")
         plugin.update_config(safe_config)
         async with get_db() as db:
-            return await self.plugin_settings_repo.set_config(db, plugin_id, plugin.config)
+            success = await self.plugin_settings_repo.set_config(db, plugin_id, plugin.config)
+        if not success:
+            raise ProxyPoolException("保存插件配置失败", 500)
+        return True
 
     def get_plugin(self, plugin_id: str) -> Optional[BaseCrawlerPlugin]:
         return registry.get(plugin_id)