Toggling site template from form submission URL performs action again

Toggling the template-overall=none from a form submission URL (that is, a URL with application/x-www-form-urlencoded data as query parameters) will trigger that action again. For instance, the move keybind navigates to a URL with parameters such as region_name and move_region, and toggling the site template after moving will attempt to move again, redirecting to page=change_region instead of simply toggling the site template as expected.

I'm not sure if we really have a way of purely toggling the site template in situations like these short of injecting the NationStates sidebar, CSS stylesheet, etc. ourselves which feels like more effort than it's really worth. But I do think we'd be better off not triggering actions again when users have already performed them and intuitively would expect a toggle to simply change the site appearance rather than performing actions again.

Start by tracing the site-template toggle and the handling of form-submission URLs, then reproduce the move keybind case with region_name and move_region parameters. Done means toggling the template changes only the site appearance and does not repeat the prior action or redirect to page=change_region.