feat(kb): blues bass cell — the KB first bass pack, 8 plays over 5 progressions (task P-41)

Boogie walkups, 8th-note ramble, Jimmy Reed R-5-6-5 shuffle, 12/8
root-fifth-octave slow burn, minor box riff (quality-resolved 3rd
self-majorizes on bVI7/V7), walking turnaround + two-beat kicks. The
maj-7 climb authored as a typed chrom-below approach (pitch derived,
offset 11 never written). KB now 172 plays. Critic PASS first try
(all 76 patterns machine-realized in C AND A; 12 prose identities
recomputed, all hold key-agnostically).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/data/kb/index.js

@@ -8,6 +8,7 @@ import bluesMeta from './blues/meta.js'
 import bluesProgressions from './blues/progressions.js'
 import bluesGuitar from './blues/guitar.js'
 import bluesPiano from './blues/piano.js'
+import bluesBass from './blues/bass.js'
 import rockMeta from './rock/meta.js'
 import rockProgressions from './rock/progressions.js'
 import rockGuitar from './rock/guitar.js'
@@ -44,7 +45,7 @@ export default {
   blues: {
     meta: bluesMeta,
     progressions: bluesProgressions,
-    instruments: { guitar: bluesGuitar, piano: bluesPiano },
+    instruments: { guitar: bluesGuitar, piano: bluesPiano, bass: bluesBass },
   },
   rock: {
     meta: rockMeta,