Don't send emails in the request thread

As it currently stands, we generally send emails directly from view methods. If something were to go wrong with the email sending, the API request would fail, even though the operation completed successfully. We should either delegate the sending of the email to a task or wrap the sending of the email in a try/catch to ensure it never disrupts the request.

Start by locating the view methods that send emails and trace how those sends affect the request response. Review the available task or error-handling patterns before choosing an approach; done means a failed email does not fail an otherwise completed API operation.

Written by the indexing model from the issue text.