Users should be able to rename files as needed inside Media Library easily.
This is kind of difficult to implement, because all references to an existing image would have to be updated in the post_content of any posts where they appear.
Here's an idea for a way around that, from Greg Schoppe on https://petitions.classicpress.net/posts/151/support-for-webp-format:
> Perhaps image tags in content could be replaced by an image shortcode, which renders based on image ID and a set of attributes.
The other option would be to add a symlink to the new file name. Most modern OSes support that, so it shouldn't be an issue whether this would happen on Unix-oid OSes or Windows (also see eg. https://blogs.windows.com/buildingapps/2016/12/02/symlinks-windows-10/ )
It would be up to the user to change any references to the old name. We can provide a quick alert/warning.
Right now, if user wants to re-name the file. They will delete current file, and upload a new file with a new name. So the problem of updating references is still there.
This is primarily to help quickly fix typos without the need to delete and re-upload files. Maybe fix image names from default names from the camera/phone to something more SEO friendly.
This would be similar to permalink slugs. It is users' responsibility to make sure they have a proper redirect from the old to the new permalinks if needed.
@viktor: Or optionally create a symlink, to avoid running in errors. Or optionally a redirect - depending on the FS allowances.
I don't know if automatic redirects would be the best thing. I hate when I have to hunt down existing slug because my post or page slug is getting -2 added. And with files, I wouldn't like unnecessary redirect.