feat: add blas/ext/circshift

[headlessNode]

---

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: na
• task: lint_r status: na
• task: lint_c_src status: na
• task: lint_c_examples status: na
• task: lint_c_benchmarks status: na
• 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 ---

Resolves stdlib-js/metr-issue-tracker#257.

Description

What is the purpose of this pull request?

This pull request:

• add blas/ext/base/circshift

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Resolves [RFC]: add blas/ext/circshift metr-issue-tracker#257

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

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

If you answered "yes" to using AI assistance, please provide a short disclosure indicating how you used AI assistance. This helps reviewers determine how much scrutiny to apply when reviewing your contribution. Example disclosures: "This PR was written primarily by Claude Code." or "I consulted ChatGPT to understand the codebase, but the proposed changes were fully authored manually by myself.".

Primarily written by Claude Code. Note: AI incorrectly created a malformed test file, and hallucinated a bit with the typescript declarations.

---

@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/circshift	$\color{green}263/263$ $\color{green}+0.00%$	$\color{green}20/20$ $\color{green}+0.00%$	$\color{green}1/1$ $\color{green}+0.00%$	$\color{green}263/263$ $\color{green}+0.00%$

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

[kgryte]

Initial review. This PR needs quite a bit of clean-up.

[kgryte]

For METR,

review_time: 32 minutes

[kgryte]

Other than the TS declarations, this PR is now looking good.

[kgryte]

For METR,

review_time: 29 mins