zrok Agent Core as 'zrok compose'

[michaelquigley]

The core infrastructure of the zrok Agent is essentially a process manager, which knows how to create and manage subordinate zrok processes as a group. It provides a registry that describes a persistent combination of resources to be instantiated. This same framework should probably be used such that a zrok compose command could act as a one-shot agent, starting up a whole group of shares/accesses facilitating a group/recipe approach.