follow stab55_13, 1. make strict runtime cache-hit validation asset/geometry based; 2. allow an extended C=4-built double cache to serve formal C=1 solve with full SHA verification; 3. record formal c128 16x32x32x48 fair speedup 8.3507x with 20/60 iterations and passing residuals; 4. document cold C=1 setup and BiCGStab caveats. [opencode].