Foundations and Methodology for a Finite-QEC Substrate: Code, Crystallisation, Ledgers, and Audit Protocol

States the foundational objects and audit methodology of the finite-QEC (quantum-error-correction) substrate program: the eight-bit local code, the bi-cubic crystallisation picture, the distinction between syndrome and strain readouts, the 28 = 2×14 service-clock construction, and the methodological rules that classify every claim as locked, computed, conditional, retired, or open. The goal is to make the companion physics papers auditable: every coefficient must name its carrier, event unit, scheduler, observable map, and reproducibility check. Version 3.0. Added a radiation-sector domain-of-validity caveat (the emergent gauge sector is an effective theory below the substrate's Brillouin scale; trans-cutoff single photons are an open foundational question) and the relativity companion citation. Copyright (C) 2026 D. G. Elliman.