test: migrate stats/base/dists/planck/stdev to ULP-based assertions

[kgryte]

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for stats/base/dists/planck/stdev from EPS-scaled relative tolerance comparisons to ULP-based assertions using @stdlib/assert/is-almost-same-value, per [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.
• removes the now unused @stdlib/math/base/special/abs and @stdlib/constants/float64/eps requires from test/test.js and test/test.native.js.

Details:

• Package converted: stats/base/dists/planck/stdev (test/test.js and test/test.native.js).
• Final ULP constant: 1 in both test/test.js and test/test.native.js.
• Measured minimum: starting from a loose bound and tightening, 1 is the smallest integer bound under which the full 1000-value fixture set passes for both the JavaScript and C implementations. At 0, 273 of the 1000 fixture assertions fail in each file (727 fixture values are bit-for-bit exact), so the bound cannot be tightened further.
• Determinism: the suite was run twice at the final bound, with the native add-on compiled locally so test/test.native.js actually executed rather than being skipped. Both runs: 1005 assertions, 1005 passing, in each of the two test files.
• Linting is clean for both files under etc/eslint/.eslintrc.tests.js, and the only changed files are the two test files.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352

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.

The conversion mirrors the idiom already used in the same family (e.g., stats/base/dists/halfnormal/stdev): the fixture loop drops the exact-vs-tolerance branch entirely in favor of a single t.strictEqual( isAlmostSameValue( y, expected[ i ], 1 ), true, 'returns expected value' ); assertion.

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.".

This PR was authored by Claude Code, running unattended as a scheduled task, which selected the package, mirrored the conversion idiom from previously merged conversions, and empirically determined and verified the minimum ULP bound.

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@stdlib-js/reviewers

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Generated by Claude Code

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/dists/planck/stdev	$\\color{green}166/166$ $\\color{green}+100.00\\%$	$\\color{green}8/8$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}166/166$ $\\color{green}+100.00\\%$

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