Material-Assets auflisten

curl "https://api.tokenlab.sh/v1/videos/assets?library_type=aigc_avatar&group_id=group-20260720123456-vrt01&page_size=20" \
  -H "Authorization: Bearer $TOKENLAB_API_KEY"

{
  "assets": [
    {
      "id": "asset-20260720123456-qn7wr",
      "object": "seedance.material_asset",
      "group_id": "group-20260720123456-vrt01",
      "library_type": "aigc_avatar",
      "asset_name": "Front view",
      "asset_type": "Image",
      "status": "ACTIVE",
      "ready": true,
      "created_at": 1782998400000
    }
  ],
  "next_page_token": null
}