BCRD: Auditable Finite Quantum Dynamics, Coarse Records, and the Present Boundary of a Quantum-Geometry Programme

BCRD (boundary-complete relational dynamics) is a finite quantum-spin research programme studying whether relationally accessible records inside a finite closed system can support their own effective dynamics. This archival v0.1 release records the reviewed programme frontier as of 14 September 2026 using a workflow that separates construction, hostile review, reconciliation, and prospective preregistration. The reviewed finite results include a sufficient finite-range mediator repair of an earlier locality failure; representative-specific native transport distinct from a Feynman-cursor control; predictive records that do not automatically self-update; exact reconstructive closure from one-known-spin erasure correction; approximate common-CPTP-map compatibility for six exposed N=8 transitions of a proper coarse record; and finite process results separating one-time coarse channels from honest semigroup dynamics. The first legal N=8 causal-break memory test remains unresolved above its apparatus floor. A direct recoupling lane establishes a model-specific adjacent-pair Racah 6j² transition probability in a historically declared pair-Lüders interface. This is explicitly not claimed to be a coherent Racah amplitude, physical F-move, pentagon/Pachner dynamics, Ponzano-Regge/Regge sector, continuum gravity, or quantum gravity. A phase-sensitive N=4 recoupling study has been prospectively frozen but no outcome from that study is included in v0.1. This deposit is intended as a durable public priority and provenance record, including explicit negative results and nonclaims. It is not a final journal manuscript and does not claim that BCRD has established quantum gravity.