Improve test coverage neat_tools/utils.h

[Jgocunha]

Summary

Add tests for the four utility functions in include/neat_tools/utils.h that currently have zero coverage.

Motivation

tests/test_utils.cpp only tests the three generateRandom*() functions. The normalization and signal-generation helpers below are exercised at runtime but never verified in the test suite, so regressions in their behaviour would go undetected.

Proposed Solution

Extend tests/test_utils.cpp with TEST_CASE blocks for:

• normalize(value, min, max) — linear normalization to [0, 1]

  • value == min → 0.0
  • value == max → 1.0
  • value at midpoint → 0.5
  • value outside [min, max] (document and assert the boundary behaviour)

• normalizeWithGaussian(value, target, width) — Gaussian-shaped score

  • value == target → maximum output (1.0)
  • value far from target → output close to 0.0
  • width = 0 edge case

• normalizeWithFlatheadGaussian(value, min, max, width) — flat-top Gaussian

  • value inside flat region → 1.0
  • value outside flat region → decreases toward 0.0

• generateRandomSignal() — returns +1 or -1

  • over 1 000 calls, only +1 and -1 are observed

Files to touch: tests/test_utils.cpp