test(workflow): reorganize specs into __tests__ and align with shared test infrastructure (#33625)

Co-authored-by: CodingOnStar <hanxujiang@dify.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

web/app/components/workflow/__tests__/candidate-node.spec.tsx

@@ -0,0 +1,40 @@
+import type { Node } from '../types'
+import { screen } from '@testing-library/react'
+import CandidateNode from '../candidate-node'
+import { BlockEnum } from '../types'
+import { renderWorkflowComponent } from './workflow-test-env'
+
+vi.mock('../candidate-node-main', () => ({
+  default: ({ candidateNode }: { candidateNode: Node }) => (
+    <div data-testid="candidate-node-main">{candidateNode.id}</div>
+  ),
+}))
+
+const createCandidateNode = (): Node => ({
+  id: 'candidate-node-1',
+  type: 'custom',
+  position: { x: 0, y: 0 },
+  data: {
+    type: BlockEnum.Start,
+    title: 'Candidate node',
+    desc: 'candidate',
+  },
+})
+
+describe('CandidateNode', () => {
+  it('should not render when candidateNode is missing from the workflow store', () => {
+    renderWorkflowComponent(<CandidateNode />)
+
+    expect(screen.queryByTestId('candidate-node-main')).not.toBeInTheDocument()
+  })
+
+  it('should render CandidateNodeMain with the stored candidate node', () => {
+    renderWorkflowComponent(<CandidateNode />, {
+      initialStoreState: {
+        candidateNode: createCandidateNode(),
+      },
+    })
+
+    expect(screen.getByTestId('candidate-node-main')).toHaveTextContent('candidate-node-1')
+  })
+})