Container Manager (cm)

For now, contains miscellaneous scripts to manage containers and container lifecycles. Eventually will evolve into a fuller-fleged application.

Notes for matt

1. implement an 'investigate' option that lets you mount a rootfs in a 'containers' dir (which is mounted in the dev container). This lets the developer debug the filesystem of a running container as needed
2. implement an 'edit' mode - this should copy the 'src' dir of a container to a 'src' dir in the local filesystem (which is mounted in the dev container). Then it should restart the container mounting the copy in place of the original. OPEN QUESTION: how do we keep the container from being gc'd after it's been shut down but before we've copied the source? Any way to exclude it from being considered by gc?
3. double-check that the dev container will work with ssh agent forwarding. alternate solution is to use something like a secrets manager, but that seems rather heavyweight.