Use a Gitea Actions workflow to deploy on push to main via
act_runner on the games VM. Switch from a Docker named volume
to a ./data bind mount for easier backup and persistence across
deploys.
Embed full assets directory and serve with via's StaticFS instead of a
custom HTTP handler. Move SQLite DB to data/c4.db for clean volume
mounting. Add multi-stage Dockerfile, docker-compose.yml, and
.dockerignore.