We want to re-architect envbuilder in a way where it can run inside an existing devcontainer image (registry.company.com/envbuilder-images/python-project:latest) and pick up and rebuild any stale layers. This also includes a Terraform data source where it can check if there is an existing registry image for a repo/branch/Dockerfile or if the bare envbuilder image needs to be started. Envbuilder will also push the newly-built image