export function contentTypeFromKey(key: string): string {
  const ext = key.split('.').pop()?.toLowerCase()
  switch (ext) {
    case 'jpg':
    case 'jpeg':
      return 'image/jpeg'
    case 'png':
      return 'image/png'
    case 'gif':
      return 'image/gif'
    case 'webp':
      return 'image/webp'
    case 'svg':
      return 'image/svg+xml'
    case 'ico':
      return 'image/x-icon'
    default:
      return 'application/octet-stream'
  }
}