fix: 完善自动导入异常中断与恢复

- 自动导入基础设施异常触发批次熔断，保留完整日志并输出安全错误信息

- 增加恢复令牌与租约围栏、无文档失败项重建及消息退避机制

- 前端展示中断状态并在状态请求失败后自动恢复轮询

- 补充批次中断迁移、配置与并发异常路径测试

easyflow-ui-admin/app/src/views/ai/documentCollection/DocumentTable.vue

@@ -85,7 +85,7 @@ const props = defineProps({
 const emits = defineEmits(['viewDoc', 'continueProcess']);
 
 const STREAM_RECONNECT_DELAY = 1500;
-const STREAM_RELOAD_DELAY = 250;
+const STREAM_RELOAD_DELAY = 3000;
 
 const pageDataRef = ref();
 const retryingDocumentIds = ref<Set<string>>(new Set());
@@ -254,7 +254,7 @@ const scheduleReload = () => {
   }
   reloadTimer = setTimeout(() => {
     reloadTimer = null;
-    pageDataRef.value?.reload?.();
+    pageDataRef.value?.reload?.({ silent: true });
   }, STREAM_RELOAD_DELAY);
 };
 
@@ -535,6 +535,7 @@ watch(
     if (disposed) {
       return;
     }
+    clearReloadTimer();
     openTaskStatusStream();
   },
 );