multiplyUnsigned hangs for multiplier >= 2^31 (>>= sign-extends) #2232

multiplyUnsigned(1, 0xFFFFFFFF);  // never returns
multiplyUnsigned(0, 2 ** 31);     // never returns

src/algorithms/math/bits/multiplyUnsigned.js:39 uses multiplier >>= 1. Bitwise ops treat the value as signed 32-bit, so once the top bit is set the arithmetic shift keeps it, and multiplier gets stuck at -1. The function is documented as unsigned multiplication. Fix: multiplier >>>= 1.

Found during an independent property-based audit of this repo (full report and reproducible harness: https://github.com/devladpopov/algorithm-autopsy/tree/main/autopsy-02).