IV.T179 — Schwinger Term from L-Holonomy at −3 ppm (NLO)

a_e^(2) = α/(2π) = (121/225)ι_τ⁴/(2π) ≈ 0.001161. The Schwinger term from single-winding vertex correction on L = S¹∨S¹. The 1/(2π) factor is the L-holonomy normalization; α enters as single-vertex EM amplitude. Structural: both α and 1/(2π) have geometric origins in the τ³ framework.