Review and improve interactions between discussion files and workflow files

[asmecher]

In the 3.3/3.4 Discussion tools, it's possible to attach files to discussions. These are tracked in the Discussion, attached to related emails (confirm), and logged in the submisison event log (confirm). However, interactions between these files and the workflow file areas are not especially fluid.

Review workflows involving discussions, and improve interactions involving files as needed.

See also: #10406