model'seedream-5.0/text-to-image' | 'seedream-5.0-lite/text-to-image' | 'seedream-5.0-lite/image-edit' | 'seedream-4.5/text-to-image' | 'seedream-4.5/image-edit' | 'seedream-4.5/sequential' | 'seedream-4.0/text-to-image' | 'seedream-4.0/image-edit' | 'seedream-4.0/sequential' required