Final revision: audit fixes, cross-scheme comparisons, known-plaintext stage

- exclude the all-ones Walsh-Hadamard row and test every key family
  against the all-ones guess
- pass the model dimension to the noise scaling so the key-length sweep
  runs at a fixed per-dimension SNR
- known-plaintext attack with nested accumulation and common random
  numbers, averaged over 40 collections
- key sensitivity and brute-force search extended to the permutation
  key and the index cipher
- make_tables regenerates all three result tables from the CSVs

data/sec_maskfam.csv

@@ -1,5 +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
+family,legit_ser,eve_ser,eve_ones_ser,mask_xcorr
+random,0.64962,0.998488,0.999988,0.2709003091
+hadamard,0.257299,0.9999905,0.9999755,0
+learned,0.2762895,0.9999285,0.99999,0.007116591092
+learned_reg,0.315952,0.9999555,0.9999175,0.01121100038