Deploy multiplayer game to server host (repo: github.com/cfoust/sour) on digitalocean/heroku from Earthfile (Docker) image

I have the source files and a Heroku/DO account. They do not support an Earthly build file and are not being deployed because I’m not sure how to convert it back to a docker file or if that’s the best route. Things I have tried: Renaming file to dockerfile Deploying from github repo Please create a helpful guide on the best way to deploy this game on either platform as the above failed, need the most efficient route. The starter questions I have for the guide are, Is there a way to build using the earthfile locally, and then use what it builds to push to the server host, what is the earthly build syntax for that? What syntax do I use in what OS to copy the existing docker image, build it locally and deploy online from my github repo? Is heroku or Digital ocean better for this, why? A discord call will work if preferred. Otherwise, you can create a comprehensive list of actions needed to deploy the game. The above two options are best to help me get started. If you are confident with the task and want to get it deployed & finished for me instead, let me know the approach you will be taking we can discuss team access after that. Thank you for looking at my inquiry!