Phase Transition Geometry on the Generator-Set Moduli Space

Paper VI of the RIME program. This paper studies generator-set deformation for sectorized operator systems. It introduces the generator-set moduli space, separates the commutativity wall Sigma_comm from normal spectral charts Sigma_spec, and studies how moving QT/HT joint spectral arrangements induce spectral and accessibility phase transitions. The paper develops three layers: global stratification of generator-set weights, local commutativity geometry at the canonical Rubik point, and the accessibility theorem layer based on the accessibility jet J_acc. Spectral walls describe changes in the joint arrangement and collision quotient; accessibility walls describe jumps in the discrete observables R1, R2, and D. This paper is part of the RIME program on spectral, transport, and accessibility structures in finite represented operator systems. Papers I--III form the initial RIME trilogy; Paper IV develops fixed collision geometry; Paper V develops the local accessibility repair calculus; Paper VII develops generic accessibility completion. Source repository: https://github.com/dooven-prime/rime-lite This work is part of the Representation-Induced Mechanics and Evolution (RIME) research program. Foundational archive DOI: 10.5281/zenodo.21108197