Export a video or carousel project. For video projects, returns MP4/MOV video files or thin FCPXML timeline metadata with container_format='mp4'/'mov'/'fcpxml'. FCPXML exports do not bundle media and may reference signed cloud URLs that expire, so relinking may be required. For carousel projects, returns ZIP archive with individual slides as JPG/PNG images. Response includes container_format and image_formats fields. Cost note: This operation may consume AI credits and can take time to complete.