refactor: align stream constructor parameter names with documentation in random/streams

[Planeshifter]

Description

What is the purpose of this pull request?

This pull request aligns the distribution parameter name in five random/streams declaration files with their own @param/@throws TSDoc and the underlying implementation. The RandomStream constructor, callable/newable, factory, and objectMode signatures named the parameter p (or k for the Student's t distribution), which did not match the documented/implemented name:

Package	Signature param	Documented & impl name
streams/exponential	p	lambda (rate parameter)
streams/poisson	p	lambda (mean)
streams/rayleigh	p	sigma (scale parameter)
streams/chisquare	p	k (degrees of freedom)
streams/t	k	v (degrees of freedom)

Each rename touches the six signature occurrences per package (constructor, new, callable, factory, the options-only factory return, and objectMode). Verified against each package's lib/main.js (function RandomStream( lambda, ... ), etc.) and its TSDoc @param/@throws tags.

Parameter names in ambient declarations are documentation only and do not affect type-checking, so this is a non-behavioral refactor; no $ExpectType/$ExpectError assertions are affected.

Related Issues

Does this pull request have any 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.

Part of a TypeScript-declaration audit of the @stdlib/random namespace, batched into a single PR at the maintainer's request. (The streams/t _sek→_sep private-member fix is handled in a separate type PR.)

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

A TypeScript-declaration audit surfaced these inconsistencies using Claude Code; each rename target was independently verified against the implementation and TSDoc, and the changes were reviewed by myself before submitting.

---

@stdlib-js/reviewers

[stdlib-bot]

Coverage Report

Package	Statements	Branches	Functions	Lines
random/streams/chisquare	$\color{green}812/812$ $\color{green}+100.00\%$	$\color{green}92/92$ $\color{green}+100.00\%$	$\color{green}15/15$ $\color{green}+100.00\%$	$\color{green}812/812$ $\color{green}+100.00\%$
random/streams/exponential	$\color{green}812/812$ $\color{green}+100.00\%$	$\color{green}92/92$ $\color{green}+100.00\%$	$\color{green}15/15$ $\color{green}+100.00\%$	$\color{green}812/812$ $\color{green}+100.00\%$
random/streams/poisson	$\color{green}812/812$ $\color{green}+100.00\%$	$\color{green}92/92$ $\color{green}+100.00\%$	$\color{green}15/15$ $\color{green}+100.00\%$	$\color{green}812/812$ $\color{green}+100.00\%$
random/streams/rayleigh	$\color{green}812/812$ $\color{green}+100.00\%$	$\color{green}92/92$ $\color{green}+100.00\%$	$\color{green}15/15$ $\color{green}+100.00\%$	$\color{green}812/812$ $\color{green}+100.00\%$
random/streams/t	$\color{green}812/812$ $\color{green}+100.00\%$	$\color{green}92/92$ $\color{green}+100.00\%$	$\color{green}15/15$ $\color{green}+100.00\%$	$\color{green}812/812$ $\color{green}+100.00\%$

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