Make it possible to use Hibernate Search Standalone and Hibernate Search with ORM in the same application

[yrodiere]

Description

Follow-up on #26182.

I tried to use both extensions in the same app, and this led to issues due to @SearchEntity-annotated classes being picked up by the Hibernate Search with ORM extension, and failing because they are not actual Hibernate ORM entities. You can find the experiment there: https://github.com/yrodiere/quarkus-quickstarts/tree/search-orm-standalone

@gsmet also pointed out that we might need adjustments on the native configuration: #39415 (comment)

Implementation ideas

We will need:

1. A way to make Quarkus understand that some entities are for the Hibernate Search + ORM extension, while others are for the Hibernate Search Standalone extension.
2. Integration tests (including native mode)
3. Maybe more: I couldn't test this very far, there may be other problems.

Addititionally we might need:

1. A third extension to regroup all common code, in particular the GraalVM substitution for org.hibernate.search.util.common.jar.spi.JandexBehavior

[quarkus-bot]

/cc @gsmet (hibernate-search)