fix: properly type extractWorkflow return (#7646)

## Summary
Type `extractWorkflow` return as `ComfyWorkflowJSON | undefined` instead
of `unknown` for better type safety downstream.

## Context
This is a small preparatory PR to slim down the Jobs API migration PR
(PR 2 of 3).

## Test plan
- [x] TypeCheck passes
- [x] Lint passes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7646-fix-properly-type-extractWorkflow-return-2ce6d73d365081c794eac3669632271f)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude <noreply@anthropic.com>

src/platform/remote/comfyui/jobs/fetchJobs.test.ts

@@ -257,35 +257,66 @@ describe('fetchJobs', () => {
   })
 
   describe('extractWorkflow', () => {
-    it('extracts workflow from nested structure', () => {
+    const validWorkflow = {
+      version: 0.4,
+      last_node_id: 1,
+      last_link_id: 0,
+      nodes: [],
+      links: []
+    }
+
+    it('extracts and validates workflow from nested structure', async () => {
       const jobDetail = {
         ...createMockJob('job1', 'completed'),
         workflow: {
           extra_data: {
             extra_pnginfo: {
-              workflow: { nodes: [], links: [] }
+              workflow: validWorkflow
             }
           }
         }
       }
 
-      const workflow = extractWorkflow(jobDetail)
+      const workflow = await extractWorkflow(jobDetail)
 
-      expect(workflow).toEqual({ nodes: [], links: [] })
+      expect(workflow).toEqual(validWorkflow)
     })
 
-    it('returns undefined if workflow not present', () => {
+    it('returns undefined if workflow not present', async () => {
       const jobDetail = createMockJob('job1', 'completed')
 
-      const workflow = extractWorkflow(jobDetail)
+      const workflow = await extractWorkflow(jobDetail)
 
       expect(workflow).toBeUndefined()
     })
 
-    it('returns undefined for undefined input', () => {
+    it('returns undefined for undefined input', async () => {
-      const workflow = extractWorkflow(undefined)
+      const workflow = await extractWorkflow(undefined)
 
       expect(workflow).toBeUndefined()
     })
+
+    it('returns undefined for invalid workflow and logs warning', async () => {
+      const consoleSpy = vi.spyOn(console, 'warn').mockImplementation(() => {})
+      const jobDetail = {
+        ...createMockJob('job1', 'completed'),
+        workflow: {
+          extra_data: {
+            extra_pnginfo: {
+              workflow: { invalid: 'data' }
+            }
+          }
+        }
+      }
+
+      const workflow = await extractWorkflow(jobDetail)
+
+      expect(workflow).toBeUndefined()
+      expect(consoleSpy).toHaveBeenCalledWith(
+        '[extractWorkflow] Workflow validation failed:',
+        expect.any(String)
+      )
+      consoleSpy.mockRestore()
+    })
   })
 })

src/platform/remote/comfyui/jobs/fetchJobs.ts

@@ -6,6 +6,8 @@
  * All distributions use the /jobs endpoint.
  */
 
+import type { ComfyWorkflowJSON } from '@/platform/workflow/validation/schemas/workflowSchema'
+import { validateComfyWorkflow } from '@/platform/workflow/validation/schemas/workflowSchema'
 import type { PromptId } from '@/schemas/apiSchema'
 
 import type {
@@ -135,12 +137,25 @@ export async function fetchJobDetail(
 }
 
 /**
- * Extracts workflow from job detail response.
+ * Extracts and validates workflow from job detail response.
  * The workflow is nested at: workflow.extra_data.extra_pnginfo.workflow
- * Full workflow validation happens downstream via validateComfyWorkflow.
+ *
+ * Uses Zod validation via validateComfyWorkflow to ensure the workflow
+ * conforms to the expected schema. Logs validation failures for debugging
+ * but still returns undefined to allow graceful degradation.
  */
-export function extractWorkflow(job: JobDetail | undefined): unknown {
+export async function extractWorkflow(
+  job: JobDetail | undefined
+): Promise<ComfyWorkflowJSON | undefined> {
   const parsed = zWorkflowContainer.safeParse(job?.workflow)
   if (!parsed.success) return undefined
-  return parsed.data.extra_data?.extra_pnginfo?.workflow
+
+  const rawWorkflow = parsed.data.extra_data?.extra_pnginfo?.workflow
+  if (!rawWorkflow) return undefined
+
+  const validated = await validateComfyWorkflow(rawWorkflow, (error) => {
+    console.warn('[extractWorkflow] Workflow validation failed:', error)
+  })
+
+  return validated ?? undefined
 }