Landscape client plugins should never exchange or run any code if they are not registered.

After the scoped resynchronization landed, it was found that some plugins would lose their data because messages that were queued before registration got dropped (an intended action).

We should rework the client not to be so reactive before registration is complete.
Currently upon startup, all plugins will register with the client machinery and react to "resynchronize" which is a message that is fired from the server even before the "registration-done" message.

We should change the client code to never run any plugin before registration.