fix: differentiate positive and negative zero in doctesting

[officiallyanee]

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Resolves none

Description

What is the purpose of this pull request?

This pull request:

fixes an issue in compareValues where signed zero (-0.0 vs +0.0) was not differentiated in doctest return value comparisons:

• Previously, numeric comparison fell through to epsdiff( actual, expected ) < 10.0. Because IEEE 754 treats -0.0 == 0.0 as true, epsdiff( -0.0, 0.0 ) evaluated to 0, causing doctests to pass when a function returned -0.0 where 0.0/+0.0 was expected (or vice versa).
• When parsed from array return annotations (e.g., [ -0 ]), numeric -0 values had their negative sign erased by String( expected ) coercion (since in JavaScript String(-0) evaluates to '0').
• When formatting error messages for TypedArray instances in compareEntries, calling map( actual, formatValue ) allocated a new typed array of the same constructor, which coerce the formatted '-0.0' string back into a numeric float and stringified it to '0', which will result in confusing error messages like Expected entries [0], but observed [0].

Related Issues

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This pull request has the following related issues:

• None

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• Read, understood, and followed the contributing guidelines.

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I used AI to understand where the issue stems from along with what are the possible fixes for it, compared some methods and reasoned to this one and checked the test cases for validness myself.

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@stdlib-js/reviewers

[kgryte]

This is definitely an improvement!

[kgryte]

@officiallyanee You marked this PR as draft. Was that intentional?

[officiallyanee]

@kgryte Yes, I got caught up in something as I was writing the PR. I drafted it out so I can come back and check once more before marking it ready for review.
It's marked ready for review now.

[kgryte]

LGTM