api.Document#getAttachmentDiff() exposes the protected XWikiAttachment instances

XWIKI-9120 has added new methods to AttachmentDiff that expose the protected XWikiAttachment instances. But AttachmentDiff is exposed to the public scripting API through api.Document#getAttachmentDiff() (used by the History UI when comparing two document versions) which means we can now access the protected XWikiAttachment instances from Velocity.

$doc.getAttachmentDiff($oldDoc, $newDoc).get(0).getOrigAttachment()