Allow archive or delete of feedback by PO/PE

during development and reviews of processes there is a lot of feedback that gets discussed and resolved that the PO/PE cannot either hide from view after resolution but also can't delete the thread, they have to keep notifying a promaster which to delete to keep the history view manageable. Additionally, any user trying to see what is currently being addressed gets lost on the litany of already resolved feedback in the Give Feedback panel. This is just far too messy to be useful and time consuming for a promaster who has a lot of other administration to do.