Embed node-red into app as server script

[lukewendling]

Similar to workers, run node-red in own loopback container. Convenient for new deployments, and also is a step towards using node-red-dashboard.

Nice-to-haves

• [ ] store flow files in shared volume or in db
• [ ] add auth to node-red editor ui
• [ ] any use for node-red-admin-cli or admin api?