Owned ("Mine") cloud plugins now offer the same local-only Delete as local
plugins: it removes the installed package and leaves the plugin in the cloud,
still reinstallable. Deleting a plugin from the cloud belongs on the plugin hub
and is no longer reachable from OrcaSlicer, so the whole cloud-delete chain is
removed down to the REST binding.
The deleted row is restored locally instead of via a blocking cloud refetch, so
it survives being offline, and it comes back without the deleted package's error
state.