The only solution is to have these files locally on the server and then use an external bind mount.
I solved this in my docker-compose-gitops-action by just inserting secrets before copying the files to the server.
https://fariszr.com/docker-compose-gitops-github/
you can't do that with dokploy even with this dokploy action so it's triggers a pull from the source repo only.
Also the preview feature on dokploy is almost useless because there is no variable to get the preview URL dynamically.