docs: add JSDoc for getRotationForIndex explaining magic number

[Arvuno]

Add JSDoc documentation for getRotationForIndex function explaining the magic number rotation logic.

[vercel]

Someone is attempting to deploy a commit to the Darshan Rajput's projects Team on Vercel.

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[Darshan3690]

Thanks for the contribution.

For future contributions, please follow the project's contribution workflow:

Open an issue first and clearly describe the problem, improvement, or feature you would like to work on.
Wait for a maintainer to review the issue and assign it to you.
After the issue is assigned, create a branch, implement the changes, and open a pull request linked to that issue.

This helps avoid duplicate work and ensures that contributions align with the project's roadmap before development begins.

Since this PR was opened without a prior assigned issue, please open an issue first for discussion next time.

Thank you for your interest in contributing. @Arvuno

[Arvuno]

Acknowledged on the issue-first workflow — got it for future contributions. The change in this PR is small (template / metadata / unused-import cleanup) and the docs pattern followed what the README already had, but I should have opened an issue first to align with your contribution policy. I'll do that going forward.

If you'd like, I can close this PR and re-open it against a tracking issue — let me know.