refactor!: update lapack/base/dlassq to use separate output arrays

[ujjwalv01]

Resolves none.

Description

What is the purpose of this pull request?

This pull request:

• refactors lapack/base/dlassq to write its scalar outputs to separate single-element arrays rather than a packed two-element out array, following the convention used by lapack/base/dladiv and lapack/base/dlaln2 (feat: add lapack/base/dlaln2 #15222).
• changes the signature to dlassq( N, X, strideX, scale, sumsq ) and dlassq.ndarray( N, X, strideX, offsetX, scale, offsetScale, sumsq, offsetSumsq ), where scale and sumsq are Float64Arrays containing a single element. Each array provides the input value and is overwritten with the updated value, mirroring the INOUT semantics of the reference Fortran routine.
• removes the return value (the function now returns void), as the routine has no matrix output.
• updates the tests, benchmarks, examples, README, REPL text, TypeScript declarations, and the lapack/base namespace declarations accordingly.

The underlying algorithm is unchanged. All previously expected values are retained in the tests, and the refactored implementation was verified to be bit-for-bit identical to the previous implementation across 200,000 randomly generated inputs spanning the small, medium, and large scaling regimes, NaN, ±Infinity, and N <= 0.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

No.

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.

This is a breaking change to the public API. Nothing merged on develop currently calls dlassq; the open PRs which do are listed in a follow-up comment below and will be updated once this lands.

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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• No

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

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Coverage Report

Package	Statements	Branches	Functions	Lines
lapack/base	$\\color{red}10747/13609$ $\\color{green}+0.00\\%$	$\\color{red}143/170$ $\\color{green}+0.00\\%$	$\\color{red}0/108$ $\\color{green}+0.00\\%$	$\\color{red}10747/13609$ $\\color{green}+0.00\\%$
lapack/base/dlassq	$\\color{red}417/419$ $\\color{green}+0.00\\%$	$\\color{red}41/42$ $\\color{green}+0.00\\%$	$\\color{green}3/3$ $\\color{green}+0.00\\%$	$\\color{red}417/419$ $\\color{green}+0.00\\%$

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

[ujjwalv01]

Note

Follow-up once this PR is merged (self-reminder) - the following open PRs call dlassq with the previous packed-out signature and need to be updated to the new ( scale, offsetScale, sumsq, offsetSumsq ) form:

• feat: add C implementation for lapack/base/dlassq #11286 - C implementation for lapack/base/dlassq (C signature, N-API bindings, and native tests need to follow this layout)
• feat: add lapack/base/dlangt #12522 - lapack/base/dlangt
• feat: add lapack/base/dlanst #12957 - lapack/base/dlanst
• feat: add lapack/base/dlanhs #13178 - lapack/base/dlanhs
• feat: add lapack/base/dlansb #13182 - lapack/base/dlansb
• feat: add lapack/base/dlansy #12837 - lapack/base/dlansy
• feat: add lapack/base/dlansp #12640 - lapack/base/dlansp
• feat: add lapack/base/dlange #7195 - lapack/base/dlange
• feat: add lapack/base/dlange #10661 - lapack/base/dlange

Nothing merged on develop calls dlassq, so no shipped code is affected.