Represents an attachment in an email message.
The filename of the attachment, which is used for display purposes and may not be the actual name of the file on disk.
readonly
content: Uint8Array | Promise<Uint8Array>
The content of the attachment as a byte array. It can be a Promise
that resolves to a Uint8Array, allowing for asynchronous loading
of the attachment content.
readonly
contentType: `${string}/${string}`
The media type of the attachment, which indicates the type of content and how it should be handled by email clients.