A Phenomenological Picard Horn Metric with Planckian Truncation: Resolving H0 Tension and SNe Ia High-z Residuals

We present a phenomenological metric ansatz embedded in a hyperbolic Picard horn topology H^3 / PSL(2, Z) modified by quantum spatial corrections. By introducing a sharp percolation transition boundary (dz = 0.0100) inspired by Loop Quantum Gravity (LQG) spin-network connectivity and an asymptotic Planckian cusp cut-off scale (z_cut ≈ 5.80), the model prevents exponential comoving distance divergence at high redshifts. Evaluating this metric against 1,590 Type Ia Supernovae from the full Pantheon+ covariance matrix yields a best-fit Hubble constant of H0 = 72.22 km/s/Mpc and total Chi2 = 1403.78, achieving strict observational parity with LambdaCDM (Delta_Chi2 = +0.08). Deriving z_cut from the LQG volume operator expectation value fixes the truncation scale theoretically, reducing free parameters to k=3 and eliminating the Bayesian information penalty. Full Python source code and analysis scripts are available on GitHub.