refactor: enhance MCP server configuration tooltips and validation messages

--bug=1054206 --user=刘瑞斌 【应用】MCP节点不配置Server config，不选择工具，可以发布应用，对话时报错 https://www.tapd.cn/57709429/s/1679457

ui/src/locales/lang/en-US/views/application-workflow.ts

@@ -228,6 +228,7 @@ export default {
       tool: 'Tool',
       toolParam: 'Tool Params',
       mcpServerTip: 'Please enter the JSON format of the MCP server config',
+      mcpToolTip: 'Please select a tool',
       configLabel: 'MCP Server Config (Only supports SSE call method)',
     },
     imageGenerateNode: {

ui/src/locales/lang/zh-CN/views/application-workflow.ts

@@ -227,7 +227,8 @@ export default {
       getTool: '获取工具',
       tool: '工具',
       toolParam: '工具参数',
-      mcpServerTip: '请输入 JSON 格式的 MCP 服务器配置',
+      mcpServerTip: '请输入JSON格式的MCP服务器配置',
+      mcpToolTip: '请选择工具',
       configLabel: 'MCP Server Config (仅支持SSE调用方式)'
     },
     imageGenerateNode: {

ui/src/locales/lang/zh-Hant/views/application-workflow.ts

@@ -227,7 +227,8 @@ export default {
       getTool: '獲取工具',
       tool: '工具',
       toolParam: '工具變數',
-      mcpServerTip: '請輸入 JSON 格式的 MCP 服務器配置',
+      mcpServerTip: '請輸入JSON格式的MCP服務器配置',
+      mcpToolTip: '請選擇工具',
       configLabel: 'MCP Server Config (僅支持SSE調用方式)',
     },
     imageGenerateNode: {

ui/src/workflow/nodes/mcp-node/index.vue

@@ -343,10 +343,21 @@ const validate = async () => {
       }
     }
   }
-  let ps = [replyNodeFormRef.value?.validate()]
-  return Promise.all(ps).catch((err: any) => {
-    return Promise.reject({ node: props.nodeModel, errMessage: err })
-  })
+  if (replyNodeFormRef.value) {
+    const form = cloneDeep(form_data.value)
+    if (!form.mcp_servers) {
+      return Promise.reject({
+        node: props.nodeModel,
+        errMessage: t('views.applicationWorkflow.nodes.mcpNode.mcpServerTip')
+      })
+    }
+    if (!form.mcp_tool) {
+      return Promise.reject({
+        node: props.nodeModel,
+        errMessage: t('views.applicationWorkflow.nodes.mcpNode.mcpToolTip')
+      })
+    }
+  }
 }
 
 onMounted(() => {