doc(command): follow rename of module.tofu

[billf]

In #80, module.tofu was renamed to module.opentofu, but the documentation was not updated to reflect this change.
As there exists a mechanism for redirecting deprecated commands, avail ourselves of it.

• fix(command): docs mismatch for module.opentofu
• chore(command): skip copy by adjusting types

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[Gogotchuri]

Thanks for catching this and taking the time to submit this PR. We appreciate community involvement.

This is a valid thing that I have overlooked, and I am OK with merging this PR.

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[Gogotchuri]

@diofeher If you also approve this, feel free to merge.

[diofeher]

Thanks for your contribution, @billf ! And good catch on refactoring the additionalHandlers code.