This way of expressing stars will have the following features:
1. !ctor & object may be dereferenced by (ap-)api
2. The activity can be referenced itself (e.g. in order to express a result of the triggered action)
3. Star is a special case of a Like. Star only happens in ForgeFed context. Different things should be named differnt ...
4. With the `source` given it would be more easy to distinguish the uri layout for object and actor id's and make implementation more straight forward
See also:
1. spec in clojure: https://repo.prod.meissa.de/meissa/activity-pub-poc/src/branch/forgefed_star/src/test/cljc/org/domaindrivenarchitecture/fed_poc/forgefed_test.cljc#L36-L41