DCRP44: Gauge-Covariant Pancake Connection and Flatness Classification

Building on DCRP43-QC's discovery that the scalar q carries residual gauge freedom, and on the defect that DCRP42's condition G=F_z+2a=0 fails to be gauge-invariant when F_q≠0, this round repairs it. It constructs the gauge-covariant connection coefficients A_z, A_s and the covariant differential operator on nondegenerate blocks, identifies two gauge-invariant primitive defects — the torsion-type C_qz and the curvature F_sz (Theorem D44.3) — and proves that when both vanish, a periodic canonical gauge exists and is unique. The new STOP (STOP-D44) is corrected to: the true canonical-pancake equality branch is the gauge-flat connection class C_qz=F_sz=0, not the original G=0; the next round, DCRP45, will test whether a finite annular PFET/strain supplier forces this flatness defect to be nonzero.