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

app/api/routes/settings.py

@@ -52,9 +52,14 @@ async def save_settings(
         validator._init_max_concurrency = request.default_concurrency
         if request.validation_targets is not None:
             validator.update_test_urls(request.validation_targets)
-        # 先关闭现有 session，再重置 semaphore，避免竞态窗口
-        await validator.close()
+        # 延迟关闭旧 session：让正在验证的代理继续使用旧 session，
+        # 新请求会通过 _ensure_session() 自动创建使用新配置的 session
+        old_session = validator._http_session
+        validator._http_session = None
+        validator._http_connector = None
         validator._semaphore = None
+        if old_session and not old_session.closed:
+            asyncio.create_task(old_session.close())
         logger.info(f"Validator config updated: timeout={request.validation_timeout}, concurrency={request.default_concurrency}, targets={request.validation_targets}")
 
     return success_response("保存设置成功", request.model_dump())