feat: add number/float16/base/signbit

[Neerajpathak07]

Resolves none.

Description

What is the purpose of this pull request?

This pull request:

• Adds number/float16/base/signbit

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• none

Questions

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No.

Other

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No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines

AI Assistance

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• No

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{{TODO: add disclosure if applicable}}

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@stdlib-js/reviewers

[Neerajpathak07]

/stdlib update-copyright-years

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
number/float16/base/signbit	$\color{green}178/178$ $\color{green}+0.00%$	$\color{green}7/7$ $\color{green}+0.00%$	$\color{green}2/2$ $\color{green}+0.00%$	$\color{green}178/178$ $\color{green}+0.00%$

The above coverage report was generated for the changes in this PR.

[Neerajpathak07]

Given that Repl error is not caused to know changes related to this PR hence I'll go ahead and open this for Review!

[Neerajpathak07]

staying consistent with the float32 to float16 conversion.

[Neerajpathak07]

@gururaj1512 Thank you for catching this!!

[kgryte]

LGTM after clean-up.

[kgryte]

As the CI failure is expected, I'll go ahead and merge.