Though we now have https://github.com/statamic/ssg/pull/137 to help with this type of workflow, the unpredictability of a shuffle only benefits the user when running concurrently with spatie/fork. This PR ensures the shuffle only happens when spatie/fork is detected.
Shuffling is intentional for balancing concurrent worker performance, but a good point was made in https://github.com/statamic/ssg/pull/136#issuecomment-1631705071 about running non-deterministically and trying to work through page errors while generating a site.
Though we now have https://github.com/statamic/ssg/pull/137 to help with this type of workflow, the unpredictability of a shuffle only benefits the user when running concurrently with spatie/fork. This PR ensures the shuffle only happens when spatie/fork is detected.