feat: add blas/base/drotmg

[DhruvArvindSingh]

Progresses #2039.

Description

What is the purpose of this pull request?

This pull request:

• Adds JS implementation of @stdlib/blas/base/drotmg
• Adds Fortran implementation of @stdlib/blas/base/drotmg
• Adds C implementation of @stdlib/blas/base/drotmg
• Adds Tests , Benchmarks and Examples for C, Fortran and JS

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• progresses [RFC]: Add BLAS bindings and implementations for linear algebra (tracking issue) #2039

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.

• In this PR i have implemented drotmg main and assign function in C with 6 and 7 arguments respectively

void c_drotmg( const double d1, const double d2, const double x1, const double y1, double *Out, const CBLAS_INT strideOut );

void c_drotmg_assign( const double d1, const double d2, const double x1, const double y1, double *Out, const CBLAS_INT strideOut, const CBLAS_INT offsetOut );

• In this PR i have implemented drotmg.f code by taking reference from LAPACK LINK

void drotmg( double *, double *, double *, const double *, double * );

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.".

{{TODO: add disclosure if applicable}}

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[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
blas/base/drotmg	$\color{red}449/497$ $\color{green}+0.00%$	$\color{red}31/34$ $\color{green}+0.00%$	$\color{green}4/4$ $\color{green}+0.00%$	$\color{red}449/497$ $\color{green}+0.00%$

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