chore: fix JavaScript lint errors - #14761

Resolves #14759

Description

What is the purpose of this pull request?

This pull request:

• This PR fixes the stdlib/no-unnecessary-nested-functions lint errors flagged in lib/node_modules/@stdlib/array/base/zip2views/lib/main.js.
• The Datum, getValue, and setValue functions were declared inside zip2views() but did not reference any of its enclosing local variables, so they have been moved to module scope.
• Since Datum is no longer re-created on every call to zip2views(), its .prototype would otherwise persist and accumulate label accessors across separate invocations, causing views from one call to leak accessors from a previous, unrelated call. To preserve the original behavior, Datum.prototype is now explicitly reset (Datum.prototype = {}) at the start of each zip2views() call, before that call's label accessors are attached.
• toJSON() was left nested, as it legitimately requires closure access to M and keys from the enclosing zip2views() call and was not flagged by the linter.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• Fix JavaScript lint errors #14759

Questions

Any questions for reviewers of this pull request?

No.

Other

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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

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