test: migrate stats/base/dists/beta/median to ULP-based assertions

[kgryte]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates the tests for stats/base/dists/beta/median from relative tolerance testing to ULP difference testing, as proposed in [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.
• replaces the delta/tol computation (tol = 15.0 * EPS * abs( expected[ i ] )) in the fixture loop with isAlmostSameValue( y, expected[ i ], 15 ).
• adds the @stdlib/assert/is-almost-same-value require and removes the now unused @stdlib/constants/float64/eps and @stdlib/math/base/special/abs requires.

The ULP bound was tightened to the measured minimum of 15 ULP. Over the full fixture set (1000 cases from test/fixtures/julia/data.json), the maximum observed ULP difference is exactly 15, attained at alpha = 17.553104872605317, beta = 17.707711393619853, where the implementation returns 0.4977657564823537 versus an expected 0.4977657564823529. A bound of 14 fails that one case, so 15 is the tightest passing integer bound. The bound was found by starting at 64 and stepping down (64 → 32 → 16 → 15 pass; 14 fails, 1 assertion). The test file was run twice at the final bound with identical results (1014 passing assertions, no failures), so the result is deterministic in this environment.

This package has no test/test.native.js and no native implementation, so only test/test.js is affected. No implementation files were modified; the only change is to the single test file.

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.

make install-node-modules could not complete in the environment used to author this change: the available registry mirror has no es-object-atoms@^1.1.2, which a transitive dependency requires. The package tests were therefore run with a standalone tape installation and NODE_PATH pointed at lib/node_modules, and the repository linter could not be run (its ESLint plugin/config chain depends on the full dev dependency tree). The changed file was checked with a reduced ESLint ruleset (unused variables, undefined references, indentation, quotes, semicolons) and is clean; the diff mirrors the idiom of the already-merged conversions in this family (e.g. stats/base/dists/f/mode, stats/base/dists/lognormal/variance, stats/base/dists/pareto-type1/kurtosis). Please confirm lint in CI.

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

This PR was authored by Claude Code running as an unattended scheduled task. The conversion mirrors already-merged migrations in the same family, and the 15 ULP bound was determined empirically by measuring the minimum passing ULP difference over every fixture rather than assumed.

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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/beta/median	$\\color{green}125/125$ $\\color{green}+100.00\\%$	$\\color{green}8/8$ $\\color{green}+100.00\\%$	$\\color{green}1/1$ $\\color{green}+100.00\\%$	$\\color{green}125/125$ $\\color{green}+100.00\\%$

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