Geometric Suppression of CP Violation in Quantum Chromodynamics from M-Theory Compactification on G₂-Holonomy Manifolds

The strong CP problem — the unexplained smallness of the QCD vacuum angle |θ̄| < 10⁻¹⁰ — is addressed within the Quantum Geometric Unification (QGU) framework, an M-theory compactification on the Joyce orbifold T⁷/(Z₃ ⋉ I*) with G₂ holonomy and Betti numbers (b₂, b₃) = (27, 451). The compactification introduces an exponential volume suppression factor e⁻ᴷ⁰ into all CP-violating observables, where K₀ = 90.005 is the dimensionless compactification volume fixed by the topological identity α⁻¹ = K₀ + (b₃/b₂)ln(b₃/b₂). The effective vacuum angle satisfies θ_eff = θ₀ × e⁻ᴷ⁰ ≈ 10⁻³⁹ θ₀, exceeding the experimental bound by 29 orders of magnitude for any bare angle θ₀ ∈ [−π, π]. The suppression mechanism operates through membrane instantons wrapping the SU(3)_C associative three-cycle, with the physical θ_eff determined at the compactification scale and perturbatively stable under RGE evolution to Λ_QCD ('t Hooft naturalness). The predicted neutron EDM |d_n| < 6.1 × 10⁻⁵⁵ e·cm lies 29 orders below the current bound. A C₃-form axion with f_a ≈ 1.2 × 10¹⁸ GeV and m_a ≈ 4.8 × 10⁻¹² eV is predicted, falling outside the standard QCD axion window — implying the non-existence of the standard QCD axion. No new symmetries, particles, or adjustable parameters are introduced. The same K₀ = 90.005 has simultaneously resolved the Hubble tension, the S₈ tension, the primordial lithium problem, the black hole information paradox, and 15 Standard Model observables in companion publications