Quarkus: Tell how to create a Jandex index in dependencies for multi-modules projects

[emmanuelbernard]

We tell people they need to generate a Jandex index https://quarkus.io/guides/cdi-reference#bean_discovery
But we don't tell them how? It would be nice to point to the doc or simply tell them right away.

Likewise telling where to create the beans.xml resources/META-INF/beans.xml would be helpful, I saw a user making the mistake.

[emmanuelbernard]

@mkouba ou even @n1hility

[gsmet]

FWIW, I wrote a comprehensive answer on Stack Overflow: https://stackoverflow.com/questions/55513502/how-to-create-a-jandex-index-in-quarkus-for-classes-in-a-external-module/55513723#55513723 .

[emmanuelbernard]

We could reference it then