fix: 优化垃圾桶异常批次缩略图

core/backend/apps/ai/views.py

@@ -295,9 +295,36 @@ class AITaskViewSet(TeamScopedViewSetMixin, ReadOnlyModelViewSet):
             if product_id:
                 product_ids.add(product_id)
 
+        # 异常批次缩略图只来自该批任务自己的成功成图。批次删除时这些资产会一起软删，
+        # 这里批量取回并按任务映射，避免逐批查询；商品封面不再参与缩略图回退。
+        preview_by_task_id = {}
+        task_ids = [task.id for task in tasks]
+        generated_assets = (
+            Asset.objects.filter(
+                team=self.get_team(),
+                origin_task_id__in=task_ids,
+                asset_type=Asset.Type.IMAGE,
+                is_deleted=True,
+                purged_at__isnull=True,
+            )
+            .prefetch_related("files")
+            .order_by("created_at", "id")
+        )
+        for asset in generated_assets:
+            files = sorted(
+                asset.files.all(),
+                key=lambda item: (not item.is_primary, item.created_at, str(item.id)),
+            )
+            for file in files:
+                preview_url = AssetFileSerializer(file).data.get("preview_url", "")
+                if preview_url:
+                    preview_by_task_id.setdefault(asset.origin_task_id, preview_url)
+                    break
+
+        # 商品仍只用于异常批次标题文字回退，不再关联或预取商品封面资源。
         products = Product.objects.filter(
             team=self.get_team(), id__in=product_ids, status=Product.Status.ACTIVE, purged_at__isnull=True
-        ).select_related("cover_asset").prefetch_related("cover_asset__files")
+        ).only("id", "title")
         product_by_id = {str(product.id): product for product in products}
 
         rows = []
@@ -307,12 +334,14 @@ class AITaskViewSet(TeamScopedViewSetMixin, ReadOnlyModelViewSet):
             first = group[0]
             payload = first.request_payload or {}
             product = product_by_id.get(str(payload.get("product_id") or ""))
-            cover = ""
-            if product and product.cover_asset and not product.cover_asset.is_deleted and product.cover_asset.purged_at is None:
-                files = list(product.cover_asset.files.all())
-                primary = next((item for item in files if item.is_primary), files[0] if files else None)
-                if primary:
-                    cover = AssetFileSerializer(primary).data.get("preview_url", "")
+            cover = next(
+                (
+                    preview_by_task_id[task.id]
+                    for task in group
+                    if task.status == AITask.Status.SUCCEEDED and task.id in preview_by_task_id
+                ),
+                "",
+            )
             intended = sum(1 for task in group if not (task.request_payload or {}).get("batch_append"))
             rows.append({
                 "id": str(first.id),