Search attachments via API

[jakubsuchy]

The API allows you to retrieve an attachment, delete and create, but there is a list operation missing so you cannot search existing attachments. All other object types have a .list method.

[tommoor]

I think we can create some version of this… though the reason it's different to other model types is because attachments belong only to the workspace. Adding a list endpoint would "reveal" all attachments that might only previously have only been visible in private documents.

One way to do it would be to only allow listing attachments that the current user has uploaded