Adds a `radicle-node` particle CUE module to simulation. Partial for
brevity in review as the `cue.mod` files found in the NEXT commit are
less relevant and autogenerated by Timoni + CUE.
Creates a set of roles: `peer`, `seed`, `bootstrap` that can be arranged
into toplogies for deployment in a k8s system. Images are provided by
Radicle Garden via quay.io.
Introduce the `simulation` directory in anticipation of migrating the
`radicle simulation network` repository. Introduce a loose plan and
explainer of how it will work.
Adrian Duke
Josh Soref
Lorenz Leutgeb