IV.P205 — Window Universality for All 7 NNLO Exponents

All 7 known NLO/NNLO correction exponents in the τ-framework decompose as rational combinations of the building block set {W₃(3)=17, W₃(4)=5, dim(τ³)=3, |lobes|=2, |sectors|=3, N_c=3}. No unexplained bare numbers appear. W₃(4)=5 enters all 7 corrections, confirming Window Universality [IV.T140]. Cross-connection: k₁−k₂ = 23/3−15/2 = 1/6 = 1/(lobes·sectors).