feat: add implementation of math/base/special/besselk0

[shubham220420]

---

type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes. report:

• task: lint_filenames status: passed
• task: lint_editorconfig status: passed
• task: lint_markdown status: passed
• task: lint_package_json status: passed
• task: lint_repl_help status: passed
• task: lint_javascript_src status: passed
• task: lint_javascript_cli status: na
• task: lint_javascript_examples status: passed
• task: lint_javascript_tests status: passed
• task: lint_javascript_benchmarks status: passed
• task: lint_python status: passed
• task: lint_r status: passed
• task: lint_c_src status: missing_dependencies
• task: lint_c_examples status: missing_dependencies
• task: lint_c_benchmarks status: missing_dependencies
• task: lint_c_tests_fixtures status: na
• task: lint_shell status: na
• task: lint_typescript_declarations status: passed
• task: lint_typescript_tests status: passed
• task: lint_license_headers status: passed ---

Progresses: #9892.

Description

What is the purpose of this pull request?

This pull request:

• adds implementation of modified bessel function of 2nd type for order 0.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Add implementation for modified Bessel function of the second kind of any real-valued order ( besselk ) #9892

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

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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• Yes
• No

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• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

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{{TODO: add disclosure if applicable}}

---

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Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/besselk0	$\color{red}400/412$ $\color{green}+0.00%$	$\color{red}23/29$ $\color{green}+0.00%$	$\color{green}5/5$ $\color{green}+0.00%$	$\color{red}400/412$ $\color{green}+0.00%$

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

[shubham220420]

Hey maintainers @kgryte & @Planeshifter since the linting failure is due to R version mismatch , therefore I'll wait for your review for further changes.