MessageAttachmentInputDto

{
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "storage_url": "https://attachments-ai.senler.ru/widget/2025/12/uuid.jpg",
    "storage_path": "widget/2025/12/uuid.jpg",
    "file_name": "screenshot.png",
    "mime_type": "image/png",
    "file_size": 1024000
}