also, if you're entirely using code-server as a remote file explorer, you might aswell setup a WebDAV share.
For the shell part, you could use shell in a box.
I know code-server can make sense but you probably won't be able to tailor it enough to your needs so you might as well use dedicated solutions for file sharing and accessing the shell.
since code-server and vscode are aimed at development use-cases, i don't think it's realistic to build what is basically a restricted server panel using it