Update stat endpoint to be able to retrieve details of a single file

In order to implement the file details pane on the frontend, there needs to be a way to fetch information about a specific file as well as a directory listing.

I propose the endpoint returns either a list of directory listings or a single directory listing depending on whether the path is a file or not.

Start by locating the stat endpoint and the code that handles directory listings. Check how the path is classified as a file or directory, then verify that the endpoint returns one file-detail listing for a file and a directory listing otherwise, supporting the frontend details pane.

Written by the indexing model from the issue text.