Returns the emails linked to a file. Emails are not included in the file record itself.

Each result has the email reference and subject; add full-records=true for every attribute. Results come 50 per page by default (10 with full-records=true, up to 250 with limit), sorted by ID, with a next URL when there are more. When the file has no linked emails, the response is {}.

To link an email, add it to the file's email_messages when creating or updating it.