feat: refine node deletion logic to protect only start nodes

web/app/dashboard/ai-workflows/_components/flowgram-editor-provider.tsx

@@ -64,7 +64,7 @@ export function useFlowgramEditorProps({
         },
         canDeleteNode: (_ctx, node) => {
           const type = String(node.flowNodeType ?? "")
-          return type !== "start" && type !== "end"
+          return type !== "start"
         },
         canDeleteLine: () => !readonly,
         onContentChange: (ctx) => {

web/app/dashboard/ai-workflows/_components/flowgram-node-registries.tsx

@@ -42,8 +42,8 @@ export function buildFlowgramNodeRegistries(nodeSpecs: AIWorkflowNodeSpec[]): Wo
       meta: {
         defaultExpanded: true,
         isStart: spec.type === "start",
-        deleteDisable: spec.type === "start" || spec.type === "end",
-        copyDisable: spec.type === "start" || spec.type === "end",
+        deleteDisable: spec.type === "start",
+        copyDisable: spec.type === "start",
         defaultPorts: defaultPortsForNodeType(spec.type),
       },
       formMeta: {

web/app/dashboard/ai-workflows/_components/workflow-editor.tsx

@@ -208,7 +208,9 @@ function WorkflowEditorInner({
 
   useEffect(() => {
     const disposable = selectService.onSelectionChanged(() => {
-      const selectedNode = selectService.selectedNodes[0]
+      const selectedNode = selectService.selectedNodes.length === 1
+        ? selectService.selectedNodes[0]
+        : null
       onSelectNode(selectedNode?.id ?? "")
     })
     return () => disposable.dispose()

web/app/dashboard/ai-workflows/_components/workflow-utils.test.mjs

@@ -252,7 +252,7 @@ describe("workflow definition mutations", () => {
     })
   })
 
-  it("deletes normal nodes and related edges while keeping start and end protected", async () => {
+  it("deletes non-start nodes and related edges while keeping start protected", async () => {
     const { deleteWorkflowNode } = await loadModule()
     const definition = {
       schemaVersion: 2,
@@ -270,6 +270,10 @@ describe("workflow definition mutations", () => {
 
     const protectedDefinition = deleteWorkflowNode(definition, "start_1")
     assert.deepEqual(protectedDefinition, definition)
+
+    const withoutEnd = deleteWorkflowNode(definition, "end_1")
+    assert.deepEqual(withoutEnd.nodes.map((node) => node.id), ["start_1", "reply_1"])
+    assert.deepEqual(withoutEnd.edges, [workflowEdge("start_1", "reply_1")])
   })
 
   it("upserts and deletes condition branches in node config", async () => {

web/app/dashboard/ai-workflows/_components/workflow-utils.ts

@@ -199,7 +199,7 @@ export function deleteWorkflowNode(
   nodeId: string
 ): AIWorkflowDefinition {
   const node = definition.nodes.find((item) => item.id === nodeId)
-  if (!node || node.type === "start" || node.type === "end") {
+  if (!node || node.type === "start") {
     return definition
   }
   return {