BCT Appendix AD3: Wolfenstein ρ and η from Hopf Fiber Geometry — Complete Unitarity Triangle Derivation

Complete technical derivation of the remaining Wolfenstein parameters ρ̄, η̄, and Rᵤt = √ (ρ̄²+η̄²), companion to BCT Letters 86, 87, and 88. Three results are established. (1) The Apex Angle Theorem: the apex of the CKM unitarity triangle lies at angle δCP = arccos (2rₒct) from the positive ρ̄-axis — a geometric consequence of the OHC Hopf fibration. (2) The Third-Generation Scale: |Vub| = exp (−SD4·rₜet· (1−3α₀) ) = 0. 003683 (Letter 88, Prediction #126), setting Rᵤt = |Vub|/ (Aλ³). (3) Tree-level predictions: Rᵤt = 0. 390 (+4. 0%), ρ̄ = 0. 161 (+8. 6%), η̄ = 0. 355 (+3. 1%), sin (2β) = 0. 718 (+2. 7%) — Predictions #127–#130. All errors share a single NLO source — the Josephson fiber correction to Rᵤt from the 8c sector — identified here and deferred to AD3 v2. The matter-antimatter asymmetry of the universe is J ∝ sin (arccos (2rₒct) ) — encoded in the octahedral void diameter. Zero free parameters.