IV.R310 — Connection to Book~II spectral gap

The emergence of hbar_tau = 1/4 is directly related to Book II's spectral gap Delta = Lambda_1 - Lambda_0 > 0; both reflect discrete eigenvalue structure forced by compact T^2, with iota_tau = 2/(pi+e) locking temporal (e-based) and spatial (pi-based) scales to yield hbar_tau = 1/4 exactly.