You can do this right now on android. If you're using chrome/chromium based browser, just visit vscode.dev and then select add to home screen from the browser menu. A similar option exists in firefox on android too, I believe.
Once you open the shortcut created from the previous step, it will open the webapp without the browser's UI.
Once you open the shortcut created from the previous step, it will open the webapp without the browser's UI.