test: migrate math/base/special/fmodf to ULP-based testing

[Planeshifter]

Resolves a part of #11352.

Description

What is the purpose of this pull request?

This pull request:

• migrates test/test.js and test/test.native.js of @stdlib/math/base/special/fmodf from relative-tolerance (EPS-based) assertions to exact-equality assertions, per the migration guidelines in [RFC]: Migrate math/base/special packages from relative tolerance testing to ULP difference testing (tracking issue) #11352.
• Independent ULP-difference computation (via @stdlib/number/float32/base/ulp-difference, with single-precision coercion of inputs and expected values exactly as performed in the tests) over all 7 fixture blocks (20004 cases) measured a maximum ULP difference of 0 for every block. As fmod is exact per IEEE 754, every assertion was therefore converted to a plain t.strictEqual( v, e, 'returns expected value' ) rather than isAlmostSameValue, following maintainer guidance that isAlmostSameValue should not be used where values are exactly equal.
• removes the now-unused EPS (@stdlib/constants/float32/eps) and absf requires and the delta/tol variables.
• Native (C) tests were built and run (not skipped) and pass with identical exact-equality assertions: no JS/C divergence was observed, so no tolerance NOTE annotations were necessary.

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.

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

This PR was written by Claude Code: an automated agent performed the test migration and computed the minimum required ULP values, and an independent adversarial verification agent recomputed the ULP values over all fixtures and reviewed the diff before opening this PR.

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@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
math/base/special/fmodf	$\\color{green}188/188$ $\\color{green}+100.00\\%$	$\\color{green}5/5$ $\\color{green}+100.00\\%$	$\\color{green}2/2$ $\\color{green}+100.00\\%$	$\\color{green}188/188$ $\\color{green}+100.00\\%$

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