Fix conflicts with X11 headers by adding #undef Unsorted

[emilk]

• Closes enum SortingStatus::Unsorted conflicts with define in X.h #7846

Some C library uses macros for constants, which makes those identifiers unusable by any other library in the same global namespace. So anyone including both X.h and rerun.hpp in the same compilation unit (in that order) would have problems. It's a dumpster-fire.

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