Quarkus OIDC support for Platform HTTP

### Describe the feature here

Users sometimes ask whether there is any support for securing REST / Platform HTTP endpoints with Quarkus OIDC. I think it'd be worth investigating whether it works.

Since it's all just Vert.x routes, I think the security parts should work OOTB. The Camel message exchange should get populated with a header containing a `QuarkusHttpUser`. From which we can get the `SecurityIdentity`, check the user name, assigned roles etc.

Might be worth creating a example project for it and maybe adding a simple bean / processor that folks can use to do simple authentication checks in their routes.