refactor: use constants/float64/nan in math/base/special/pow

[ujjwalv01]

Resolves a part of #11743.

Description

What is the purpose of this pull request?

This pull request:

• Replaces inline NaN generation (0.0/0.0) in math/base/special/pow with the stdlib NaN constant from @stdlib/constants/float64/nan.
• Adds the necessary #include "stdlib/constants/float64/nan.h" directive to the C source file.
• Updates the manifest.json configurations to add @stdlib/constants/float64/nan as a dependency.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: replace inline NaN generation with stdlib NaN constants in C source files (tracking issue) #11743

Questions

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No.

Other

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No.

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• Read, understood, and followed the contributing guidelines.

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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/pow	$\\color{red}1380/1382$ $\\color{green}+0.00\\%$	$\\color{red}119/120$ $\\color{green}+0.00\\%$	$\\color{green}11/11$ $\\color{green}+0.00\\%$	$\\color{red}1380/1382$ $\\color{green}+0.00\\%$

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

[kgryte]

LGTM

[kgryte]

As the CI failure is not due to changes introduced in this PR, I'll go ahead and merge.