feat: added accessor protocol to meanpn

[dhruvilmehta]

Resolves #5650

Description

What is the purpose of this pull request?

This pull request:

• Added accessor protocol to meanpn.

Related Issues

Does this pull request have any related issues?

This pull request:

• resolves [RFC]: refactor and add protocol support to stats/base/meanpn #5650

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.

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Coverage Report

Package	Statements	Branches	Functions	Lines
stats/base/meanpn	$\color{green}312/312$ $\color{green}+100.00\%$	$\color{green}17/17$ $\color{green}+100.00\%$	$\color{green}3/3$ $\color{green}+100.00\%$	$\color{green}312/312$ $\color{green}+100.00\%$

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