feat: introduce trigger functionality (#27644)

Signed-off-by: lyzno1 <yuanyouhuilyz@gmail.com>
Co-authored-by: Stream <Stream_2@qq.com>
Co-authored-by: lyzno1 <92089059+lyzno1@users.noreply.github.com>
Co-authored-by: zhsama <torvalds@linux.do>
Co-authored-by: Harry <xh001x@hotmail.com>
Co-authored-by: lyzno1 <yuanyouhuilyz@gmail.com>
Co-authored-by: yessenia <yessenia.contact@gmail.com>
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web/app/components/rag-pipeline/hooks/use-pipeline-init.ts

@@ -60,7 +60,10 @@ export const usePipelineInit = () => {
       if (error && error.json && !error.bodyUsed && datasetId) {
         error.json().then((err: any) => {
           if (err.code === 'draft_workflow_not_exist') {
-            workflowStore.setState({ notInitialWorkflow: true })
+            workflowStore.setState({
+              notInitialWorkflow: true,
+              shouldAutoOpenStartNodeSelector: true,
+            })
             syncWorkflowDraft({
               url: `/rag/pipelines/${datasetId}/workflows/draft`,
               params: {