feat: 生图模型可选(火山/gpt-image) + 工作台图「加入资产库」收纳 + 任务中心排序修复

- AI 工作室生图支持显式选模型:resolve_image_model 解析 volcano(Seedream 图生图,
  无 image_edit 时走 image_generation 带参考图)/ gpt-image(image_edit 多图编辑),
  未选回落系统默认;enqueue_standalone_images 透传 image_model
- 资产库收纳:Asset 加 in_library 字段(迁移 0007,既有资产 db_default=True 不动);
  工作台生成图默认 in_library=False,只在工作台展示,用户「加入资产库」后才进库列表;
  assets 视图/序列化器/library 页/types 配套
- 任务中心修复:AITaskViewSet 默认 order_by(-created_at),前端 aiTasks 取 page_size=200。
  原因:列表无排序时 MySQL 按 UUID 主键乱序返回,把一批旧失败记录顶到首页,
  前端又只取首页 20 条算 全部/已完成/失败 → 误显示「全部失败」(实为 421 成功/少量失败)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/backend/tryon_volcano_test.py

@@ -0,0 +1,63 @@
+"""内衣·真人上身:换火山 Seedream 生图模型,看会不会被审核拦(对照 gpt-image-2 的 sexual 拦截)。
+跑法: .venv/bin/python tryon_volcano_test.py
+产物: /Users/maidong/Desktop/zyc/volcano_test
+"""
+import os
+import django
+
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "airshelf.settings.development")
+django.setup()
+
+from apps.products.models import Product  # noqa: E402
+from apps.assets.models import Asset  # noqa: E402
+from apps.ai.models import ModelConfig  # noqa: E402
+from apps.ai.services import (  # noqa: E402
+    get_image_provider, build_model_tryon_prompt_refs, _product_reference_urls, _asset_preview_url,
+)
+from apps.ai.providers.volcano import VolcanoArkProvider  # noqa: E402
+
+PRODUCT_ID = "42078cdc-8714-4fc7-be5c-6aa42b7fc995"   # 棉居莫代尔无痕内衣
+MODEL_ID = "ad362810-cf3e-49c0-9426-8142a74b75b2"     # 真人模特
+OUT_DIR = "/Users/maidong/Desktop/zyc/volcano_test"
+# 试两个版本(从新到旧),哪个可用用哪个
+VOLCANO_MODELS = ["doubao-seedream-5-0-260128", "doubao-seedream-4-5-251128"]
+
+
+def main():
+    os.makedirs(OUT_DIR, exist_ok=True)
+    p = Product.objects.get(id=PRODUCT_ID)
+    product_urls = _product_reference_urls(p, limit=3)
+    model_url = _asset_preview_url(Asset.objects.get(id=MODEL_ID))
+    images = product_urls + [model_url]
+    prompt = build_model_tryon_prompt_refs(p, has_model=True, base_prompt="", index=0, n_product=len(product_urls))
+    print(f"商品: {p.title} | 类目: {p.category} | 商品图数: {len(product_urls)} + 模特图")
+    print(f"提示词:\n{prompt}\n")
+
+    for mname in VOLCANO_MODELS:
+        mc = ModelConfig.objects.filter(capability="image", name=mname).first()
+        if mc is None:
+            print(f"⚠️ 库里没有模型配置 {mname},跳过")
+            continue
+        provider = get_image_provider(mc)
+        print(f"\n━━━ 火山 {mc.provider.name}:{mname} ━━━")
+        try:
+            # Seedream 多图参考走 image 参数(可传 URL 列表);size 用 2K
+            resp = provider.image_generation(model=mname, prompt=prompt, image=images, size="2K")
+            media = provider.extract_first_media_url(resp)
+            fileobj, ct = VolcanoArkProvider.media_to_bytes(media)
+            ext = ".jpg" if "jpeg" in ct else (".webp" if "webp" in ct else ".png")
+            path = os.path.join(OUT_DIR, f"volcano_{mname}{ext}")
+            with open(path, "wb") as f:
+                f.write(fileobj.getvalue())
+            print(f"✅ 出图成功 → {path}")
+            break
+        except Exception as exc:  # noqa: BLE001
+            msg = str(exc)
+            flagged = any(k in msg.lower() for k in ("moderation", "safety", "sexual", "blocked", "sensitive", "审核", "违规", "content"))
+            print(f"❌ 失败{' · 命中内容审核' if flagged else ''}: {msg[:600]}")
+
+    print(f"\n完成。产物: {OUT_DIR}")
+
+
+if __name__ == "__main__":
+    main()