Quantum Structural Theory of Harmony (QSTH 6.6) – Planckian Horizon 2.0 as an operational entropic-coherence principle

QSTH 6.6 is the BASE (core) Zenodo record for the S_eff Horizon test framework developed within Planckian Horizon 2.0. The record introduces no new invariant; instead it consolidates operational definitions, a regime-frozen sign/uniqueness discipline, and a skeptic-friendly FM1–FM4 audit contract (unit consistency, null/mocks collapse, overlap convergence, and anti-tuning rules). Its purpose is to enable a falsification-first test on public Event Horizon Telescope (EHT) data—primarily M87* (SR1), with a direct extension path to Sgr A*. Reproducibility is anchored by (i) a complete SR1 data pack (UVFITS + CSV/TXT products, manifests, and SHA256 checksum lists) and (ii) a FULL-2 cross-pipeline runbook anchor specifying independent reconstructions in DIFMAP / eht-imaging / SMILI together with required audit outputs (maps, logs, parameters, and environment export). Interim results (FAST gate and FULL-lite(+/++) checks) are included only as supportive status evidence and do not constitute an empirical verdict. A final PASS / INCONCLUSIVE / FAIL claim is explicitly reserved for the FULL-2 cross-pipeline runs on SR1 UVFITS, extraction of a unified ring-scale metric θring±σθring±σθring±σ, and overlap convergence consistent with FM1–FM4. This record therefore functions as a public, audit-ready blueprint for community replication: it reports where the project currently stands and specifies the single remaining decisive step required for a verdict. Related QSTH Zenodo records (recommended entry points). QSTH 1.0 — Foundational Publication (DOI: 10.5281/zenodo.17455814) QSTH 1.0 — Horizon Set (DOI: 10.5281/zenodo.18015679) QSTH 4.1 — Planckian Horizon 2.0 (DOI: 10.5281/zenodo.17899867) QSTH 6.5 — Planckian Horizon (DOI: 10.5281/zenodo.18649631)