Occasionally we get reports of people that build blender and end up with either build errors or end up with builds that do not run on other systems. The root cause is when you install vpckg and integrate it into the build system it puts the search path for its includes and libraries before anything else. previously we told people to either uninstall vcpkg or remove the conflicting packages, which was not great. this change opts out of the use of vcpkg for blender only, so people can keep using it for other work without issues.