This setup is made for locale development. As stated in the FAQ, XAMPP is not meant for production.
To use VSCode you have a couple of options. You can mount the
/opt/lampp directory from the Volumes tab in the Stackman manager. This will mount the directory to your machine. Then you can run
df in a terminal in your OS X (not the one in Stackman) to know where it was mounted:
$ df -h
192.168.64.3:/opt/lampp 15Gi 1.9Gi 12Gi 14% 68035 909245 7% /Users/amorenoc/.bitnami/stackman/machines/xampp/volumes/root
In my case it was mounted to
/Users/amorenoc/.bitnami/stackman/machines/xampp/volumes/root, so from the same terminal you can run:
$ sudo code /Users/amorenoc/.bitnami/stackman/machines/xampp/volumes/root
To open the folder in VSCode.
Another option would be to configure VSCode to connect to the virtual machine using SSH. You can read more about this here: https://code.visualstudio.com/docs/remote/ssh