conformance testing CI/CD support #4
Description
- refactor the devcontainer Dockerfile to have a dev and runtime/CI stage with a shared root dependency stage that lays down all the testing dependencies
- determine how best to accommodate pluggable model load and auth when using, e.g., inline files in runtime/CI stage, only env var https://github.com/trolie/conformance/blob/main/test/helpers.py#L157