Use explicit discriminants for QueryOriginKind for better comparisons

[Veykril]

This won't really have an observable effect as its really micro-optimizing the tiniest thing ever, but given we already have a very specialized layout here we might as well push it to the limits.

This means if comparing for either Derived and DerivedUntracked in the same branch, instead of getting

        cmp     dil, 3
        sete    cl
        test    dil, dil
        sete    al
        or      al, cl

we get

        cmp     dil, 2
        setae   al

as we now only need to check a single bit

[netlify]

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[codspeed-hq]

CodSpeed Performance Report

Merging #913 will not alter performance

_{Comparing Veykril:veykril/push-umpmpprylxyz (28983b8) with master (04053c1)}

Summary

✅ 12 untouched benchmarks