Moderation policy clarification around hiding comments

Our moderation policy says this:

Moderate means to modify, lock, or delete one or more Posts to correct or address Code of Conduct violations.

Note that it includes modify, lock, and delete, but not hiding. That was (IIRC) intentional. We want people to be able to hide off-topic comments without needing to engage in the overhead of opening an issue in the moderation repo or leaving a comment in the issue that they are hiding the comment in (as that defeats the purpose of hiding the comment in a lot of cases).

The policy also says:

Collaborators may use the Hide feature in the GitHub interface for off-topic posts by non-Collaborators.

We don't (as far as I see right now, at least) say that hiding off-topic posts by non-Collaborators is not considered a moderation action and therefore does not require the overhead of opening an issue in the moderation repo or otherwise announcing that you've moderated a comment.

If there's agreement that I have this right, then we should update the policy to amke that point clear.

@nodejs/moderation

Locate the moderation policy containing the quoted definitions and the Hide feature guidance. Review the surrounding policy language, then clarify whether hiding off-topic posts by non-Collaborators is outside the moderation-action requirements. Done means the policy clearly states the intended distinction without changing the existing guidance.