Show an effect (glow) when a new item is created in the current working directory

[jelly]

This was a comment in the symlinks PR, currently there is no visual indication when you created a new directory for example, upload a new file or create a new file.

[garrett]

We talked about a glow (like we use elsewhere in Cockpit), perhaps a toast, perhaps both... or something else. TBD (to be decided/discussed/designed/other-d-words).