fix: handle failed async downloads in upload dialog watcher

Watch the download task's status directly instead of only
lastCompletedDownload, so failed/errored tasks also transition
the dialog out of 'processing' state.

src/platform/assets/composables/useUploadModelWizard.test.ts

@@ -131,4 +131,56 @@ describe('useUploadModelWizard', () => {
     // BUG: uploadStatus should be 'success' but remains 'processing'
     expect(wizard.uploadStatus.value).toBe('success')
   })
+
+  it('updates uploadStatus to error when async download fails', async () => {
+    const { assetService } =
+      await import('@/platform/assets/services/assetService')
+
+    const asyncResponse: AsyncUploadResponse = {
+      type: 'async',
+      task: {
+        task_id: 'task-fail',
+        status: 'created',
+        message: 'Download queued'
+      }
+    }
+    vi.mocked(assetService.uploadAssetAsync).mockResolvedValue(asyncResponse)
+
+    const wizard = useUploadModelWizard(modelTypes)
+    wizard.wizardData.value.url = 'https://civitai.com/models/99999'
+    wizard.selectedModelType.value = 'checkpoints'
+
+    await wizard.uploadModel()
+    expect(wizard.uploadStatus.value).toBe('processing')
+
+    // Simulate WebSocket: download fails
+    const { api } = await import('@/scripts/api')
+    const handler = vi
+      .mocked(api.addEventListener)
+      .mock.calls.find((c) => c[0] === 'asset_download')?.[1] as
+      | ((e: CustomEvent) => void)
+      | undefined
+
+    const failEvent = new CustomEvent('asset_download', {
+      detail: {
+        task_id: 'task-fail',
+        asset_id: '',
+        asset_name: 'model.safetensors',
+        bytes_total: 1000,
+        bytes_downloaded: 500,
+        progress: 50,
+        status: 'failed' as const,
+        error: 'Network error'
+      }
+    })
+
+    if (handler) {
+      handler(failEvent)
+    }
+
+    await nextTick()
+
+    expect(wizard.uploadStatus.value).toBe('error')
+    expect(wizard.uploadError.value).toBe('Network error')
+  })
 })

src/platform/assets/composables/useUploadModelWizard.ts

@@ -249,12 +249,22 @@ export function useUploadModelWizard(modelTypes: Ref<ModelTypeOption[]>) {
         uploadStatus.value = 'processing'
 
         const stopWatch = watch(
-          () => assetDownloadStore.lastCompletedDownload,
-          async (completed) => {
-            if (completed?.taskId === result.task.task_id) {
+          () =>
+            assetDownloadStore.downloadList.find(
+              (d) => d.taskId === result.task.task_id
+            )?.status,
+          async (status) => {
+            if (status === 'completed') {
               uploadStatus.value = 'success'
               await refreshModelCaches()
               stopWatch()
+            } else if (status === 'failed') {
+              const download = assetDownloadStore.downloadList.find(
+                (d) => d.taskId === result.task.task_id
+              )
+              uploadStatus.value = 'error'
+              uploadError.value = download?.error || 'Download failed'
+              stopWatch()
             }
           }
         )