Separate main code and debugging code

[Zelaven]

Debugging code is essentially an application of the main code and can be split.
This should include an option to build the system with the debugging code enabled. It would make sense in this case that the source code is omitted as it is a feature of the build system that is targeted toward testing, modifying and rebuilding rather than for releases, which means that the source is already available in the use context of the feature.