Restore Jandex on processes quarkus extension + lazily initialize DataIndexEventPublisher

Jandex plugin is missing from the process extension.

While implementing the new API this caused weird startup issues (classes could not be injected).

By plugging jandex again, the dev services are instantiated. But if the config property for the data index is not set, then it errors out.

We must refactor the event emitter so that it does not breaks