feat: enable CI/CD

[kevin-secrist]

1. Builds the Dockerfile and pushes to GHCR so it can be shared. One issue I've run into in the past is the Dockerfile becoming out-of-date and I'm unable to develop without fixing it. With an image pushed to the registry, at least there'll be a working image to start with.
2. Builds the docs in GHA so it can be previewed without actually needing to develop locally, for basic changes
3. Builds and automatically creates a release whenever there's a push to main, and automatically uploads the artifacts for the build to that release.