Feature Request: Edit filenames in media manager

At the moment it isn't possible to edit filenames (images etc.) in media manager
Would be a good feature.

The issue names the media manager but no file or test. Start by locating its implementation and existing filename handling, then confirm how media changes are persisted. Done means a user can edit and save an image or other media filename and see the updated name in the manager.

Written by the indexing model from the issue text.