See https://github.com/wildfly/wildfly/pull/15965#issuecomment-1245134740 for some background.
When we provision a slimmed server using Galleon layers, the Hibernate Search modules are not provisioned, as nothing requires them. (This differs from a complete Galleon provisioning run, which provisions all modules.)
We should work out a clean way to allow the necessary modules to be provisioned.
My assumption is this would be done via a new 'hibernate-search' layer. It would likely depend on the 'jpa' layer (which brings the jpa subsystem into the config), and would primarily serve to add all the Hibernate Search modules that are present in the standard server zip.
Potentially we could get more fine grained, with layers for the different search backends, with 'hibernate-search' optionally depending on those (to allow any unwanted one to be excluded). But that level of granularity is more than we have done up to now with our layers. If we just provision all the modules that came in our standard zip, we can also add finer-grained excludable layers later if there is real demand.