docs: managing containers

[jtagcat]

https://overnode.org/docs/overnode-yml-file-description

id property is an unique within a cluster identifier of a project. Overnode can manage multiple projects in the same cluster and the id field value allows to identify a project.

although it is linked to, the fact that multiple 'projects' (the concept is never explained) can be shall be mentioned. I got the impression that the id meant 'cluster name'

[avkonst]

Agree. Multiple projects concept should be explained in the workflow essentials.