Also, I'm a little bit wondering at how much all of this is really copyrightable in the end. Because if you keep it private I understand, but here it is basically for each package just a few lines, recipes to build the components that they don't own. Like trying to copyright the line "make build".
And it might be each the single and obvious way to package the thing anyway.
And speaking at the built artefacts, usually a binary distribution of third party open source software with common license should preserve the same rights to the user to access the source code, the instructions to build, and the right to redistribute...