Keyed masking for secure multi-user semantic communication

Reproducibility package for the TIFS submission: transmit and receive
core, security stages (eavesdropper, jamming, key families, attack
difficulty, known-plaintext), real BERT token streams, closed-form
verification, and the scripts that regenerate every figure and table
from the released CSVs.

data/sec_maskfam.csv

@@ -0,0 +1,5 @@
+family,legit_ser,eve_ser,mask_xcorr
+random,0.64962,0.998488,0.2709003091
+hadamard,0.2568,0.9995605,0
+learned,0.2762895,0.9999285,0.007116591092
+learned_reg,0.315952,0.9999555,0.01121100038