WildFly produces and tests 3 separate feature packs, and will likely add a fourth next year for legacy EE 10 support in std WF.

We need a cleaner organization of the build and testsuite execution so the base and expansion parts can be independently built, and, more importantly, can be independently tested.

This is particularly important downstream, where channel-manifest driven test executions are common and there are more scenarios people may want to execute only the base tests or only the expansion tests. It's also more likely that users may want to build only the base parts.

There can be upstream benefits to this as well though. At a minimum doing it clarifies the relationships between the elements of our build, where right now some things happen as a result of luck. It can also make possible things like parallelization of work in CI; e.g. build the base server and then in parallel kick off the base server tests and the expansion build.