squareRoot(6) returns 3, squareRoot(12) returns 4; test expects squareRoot(3, 1) = 1.8 (correct: 1.7) #2231

src/algorithms/math/square-root/squareRoot.js stops Newton's iteration when |number - root²| <= 10^-tolerance (line 31). That bounds the error of the square, not of the root. Newton's method approaches √n from above, so the loop stops on an overestimate, and rounding then goes the wrong way.

squareRoot(6);     // 3     expected 2   (√6 = 2.449)
squareRoot(12);    // 4     expected 3   (√12 = 3.464)
squareRoot(3, 1);  // 1.8   expected 1.7 (√3 = 1.732)

squareRoot.test.js:30 asserts expect(squareRoot(3, 1)).toBe(1.8), so the test enshrines the bug. For n = 0..3000 and tolerance 0..6 there are 68 wrong results.

Fix: iterate until the root stops decreasing (while (next < root)), then round. Checked on 259,695 inputs against correctly rounded Math.sqrt; the only mismatches are 53 last-digit float effects at tolerance >= 10. This also removes the hang reported in #2187 (squareRoot(65549, 11)). The #2187 change alone still returns 3 and 1.8.

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).