MacOS – accidentally deleted /var folder

Having a bit of trouble following your description of the situation. It'd be helpful if you used actual path names instead of "The one in my user folder" type descriptions.

You have a backup right? Ok then...

The sidebar link is just a shortcut, so it doesn't really mean anything by itself. Fix that last. Just delete it and then re-add it.

Run a disk check and permission repair if you haven't already.

If ~/Desktop doesn't exist and you're sure it was some how renamed .tsclient, use terminal to move/rename it back. I think its more likely that your ftp client uses that as a temp location and that the files there are only partially downloaded though.

If ~/Desktop does exist then just move the folder contents back where they belong not the folder itself. Then delete and re-add to the sidebar

Do you remember some of the filenames?

Try to enable Spotlight to search documents, and use it to find the file you misplaced. You should be able to find it if it’s still inside your Documents folder.

Using Terminal

My last attempt would be using Terminal to list all the files containing your files content keywords. Run Terminal and enter command below (replace your file content with some of the unique keywords in your lost documents:

grep -R 'your file content' *

It should display all the file it can find on your User folder. If it still can’t find the files, they’re most likely gone forever.