fix: nullable failure_reason, factory fixture for sft store tests

web/src/stores/sft.test.ts

@@ -3,7 +3,8 @@ import { useSftStore } from './sft'
 import type { SftQueueItem } from './sft'
 import { beforeEach, describe, it, expect } from 'vitest'
 
-const MOCK_ITEM: SftQueueItem = {
+function makeMockItem(overrides: Partial<SftQueueItem> = {}): SftQueueItem {
+  return {
     id: 'abc',
     source: 'cf-orch-benchmark',
     benchmark_run_id: 'run1',
@@ -25,6 +26,8 @@ const MOCK_ITEM: SftQueueItem = {
     node_id: 'heimdall',
     gpu_id: 0,
     tokens_per_sec: 38.4,
+    ...overrides,
+  }
 }
 
 describe('useSftStore', () => {
@@ -38,37 +41,37 @@ describe('useSftStore', () => {
 
   it('current returns first item', () => {
     const store = useSftStore()
-    store.queue = [MOCK_ITEM]
+    store.queue = [makeMockItem()]
     expect(store.current?.id).toBe('abc')
   })
 
   it('removeCurrentFromQueue removes first item', () => {
     const store = useSftStore()
-    const second = { ...MOCK_ITEM, id: 'def' }
-    store.queue = [MOCK_ITEM, second]
+    const second = makeMockItem({ id: 'def' })
+    store.queue = [makeMockItem(), second]
     store.removeCurrentFromQueue()
     expect(store.queue[0].id).toBe('def')
   })
 
   it('restoreItem adds to front of queue', () => {
     const store = useSftStore()
-    const second = { ...MOCK_ITEM, id: 'def' }
+    const second = makeMockItem({ id: 'def' })
     store.queue = [second]
-    store.restoreItem(MOCK_ITEM)
+    store.restoreItem(makeMockItem())
     expect(store.queue[0].id).toBe('abc')
     expect(store.queue[1].id).toBe('def')
   })
 
   it('setLastAction records the action', () => {
     const store = useSftStore()
-    store.setLastAction('discard', MOCK_ITEM)
+    store.setLastAction('discard', makeMockItem())
     expect(store.lastAction?.type).toBe('discard')
     expect(store.lastAction?.item.id).toBe('abc')
   })
 
   it('clearLastAction nulls lastAction', () => {
     const store = useSftStore()
-    store.setLastAction('flag', MOCK_ITEM)
+    store.setLastAction('flag', makeMockItem())
     store.clearLastAction()
     expect(store.lastAction).toBeNull()
   })

web/src/stores/sft.ts

@@ -12,7 +12,7 @@ export interface SftQueueItem {
   model_response: string
   corrected_response: string | null
   quality_score: number          // 0.0 to 1.0
-  failure_reason: string
+  failure_reason: string | null
   task_id: string
   task_type: string
   task_name: string