Expands the NR bracket from a pure Cartan-connection lemma to a unified
proposal covering six formerly separate layers:
Core: [mu,mu]_NR = 0 (Layer 2c, new code)
YB: Yang-Baxter integrability via Sidon-disjoint blocks
TL: Temperley-Lieb quotient factorization
Analytic: Eigensolid convergence as the analytic dual
PIST: Same Sidon support separation drives classification gates
VCN: Zero-gap encoding = vanishing NR terms as structural signal
Each connection shows independent work — the specific argument, the
Layer-1 invariant that powers it, and what fails if the mechanism
breaks.