Deleted assets still on disk

Hi ,
Is there a tool, menu option or safe way to clear these reference files and deleted folders? Naturally I understand the risk involved in purging reference files that are used to redirect assets on map files that have not been opened but is there a way to clear these files from the content folder?

The reason I ask is that currently I am rapid prototyping which means Folder structures change and asset names change a lot. And it is painful to add files to my P4 Depot. Since I find myself sifting thur 40+ deleted or moved files in a folder that in the editor only contains 6 assets.

The other inconvenience is renaming a file the same as a file I have just deleted in the same folder structure. It can’t be done. I have a lot of renamed files with a 1 or a 2 attached to the back of the name because those invisible reference files still live in the folder even though they aren’t visible in the editor. It makes sense why this is happing since both a reference file and actual file can’t have the same name in the same directory, but it is cumbersome and confusing to constantly have to rename files with new and unique names.

As a project develops I could see this problem growing into a really large elephant.

Some suggestions:
Unreal could place all those reference files in a single folder or mirrored structure outside of the content folder or a tool could re-path all the assets of unopened maps before the files are purged.