Code and data for "Approximation-fragile width phases and the failure of Floquet entanglement spectra in a driven BHZ ribbon"

Code, archived numerical data, and the fifteen source figure files of the six manuscript figures. The deposit contains the exact Sambe-Floquet quasienergy scans across the critical widths (J1), the single-particle entanglement-spectrum scans (J2, five pipelines including the torus control), the entanglement wave-function and entropy scan (M1), the kwant two-terminal transport scans (N1), the drive-amplitude spin-valve scan (N2), verification scripts (F3/D/S1/A1-A5/A9), and a figure-regeneration script that rebuilds all manuscript figures from the archived JSON without recomputation.