feat: add additional nodeCascaderRefs for enhanced validation

--bug=1064068 --user=刘瑞斌 【工作流知识库】文档分段节点高级分段时，分段长度、自动清洗选项切换参数引用方式会互相影响 https://www.tapd.cn/62980211/s/1806124

Author: liuruibin

ui/src/workflow/nodes/document-split-node/index.vue

@@ -335,12 +335,18 @@ const aiChatNodeFormRef = ref<FormInstance>()
 const nodeCascaderRef = ref()
 const nodeCascaderRef2 = ref()
 const nodeCascaderRef3 = ref()
+const nodeCascaderRef4 = ref()
+const nodeCascaderRef5 = ref()
+const nodeCascaderRef6 = ref()
 
 const validate = () => {
   return Promise.all([
     nodeCascaderRef.value ? nodeCascaderRef.value.validate() : Promise.resolve(''),
     nodeCascaderRef2.value ? nodeCascaderRef2.value.validate() : Promise.resolve(''),
     nodeCascaderRef3.value ? nodeCascaderRef3.value.validate() : Promise.resolve(''),
+    nodeCascaderRef4.value ? nodeCascaderRef4.value.validate() : Promise.resolve(''),
+    nodeCascaderRef5.value ? nodeCascaderRef5.value.validate() : Promise.resolve(''),
+    nodeCascaderRef6.value ? nodeCascaderRef6.value.validate() : Promise.resolve(''),
     aiChatNodeFormRef.value?.validate(),
   ]).catch((err: any) => {
     return Promise.reject({ node: props.nodeModel, errMessage: err })