nx_sketch_comparator.nx

sketch_comparator.nx -- sealed-verdict comparator for head-to-head stomp claims. THE VALIDATION PRIMITIVE. Every claim of the form "our primitive beats incumbent X on axis Y" must pass through this. Sealed verdicts: NX_CMP_VERDICT_BEATS our primitive measurably better NX_CMP_VERDICT_EQUIVALENT within tolerance band; can't distinguish NX_CMP_VERDICT_LOSES incumbent measurably better NX_CMP_VERDICT_INCONCLUSIVE missing data or degenerate inputs THREE INDEPENDENT AXES: ACCURACY -- whoever's closer to ground truth wins MEMORY -- smaller bytes wins TIME -- faster wall-time wins COMPOSITE verdict aggregates 3 axis verdicts via majority vote with inconclusive-axis discounting. A 2/3 majority with one INCONCLUSIVE is enough to call. A 1/1/1 tie returns EQUIVALENT. All inputs are i64; caller supplies measurements from external runs. This primitive does NOT itself run benchmarks -- it normalizes the VERDICT against typed tolerance, so claims become falsifiable. LOSSLESS-LANGUAGE DISCIPLINE: result struct carries verdict + signed delta in PPM (positive = our wins) + ppb confidence.