This is a regular need to call DRC from python or commandline.
There is a issue on python DRC wrapping here : https://gitlab.com/kicad/code/kicad/-/issues/2030
Some workarounds discussed here : DRC from Python Scripting
QA pcbnew tools are only able to run “courtyard_overlap” and “courtyard_missing” rules check not main DRCs.
I think that the first step would be to separate GUI code from execution code in DRC class.
If the new “DRC_EXEC” class inherit from “DRC_TEST_PROVIDER” class, it would be easily ran from QA tools.
1- Is this approach in line with product targets ?
2- If I realize such patch (folowing code guidelines) would if be integrated as I may not get up to python interface ? (commandline qa_tools may be enought for my need)