fix: header/footer undo history across story sessions#2935

harbournick merged 3 commits intomainsuperdoc-dev/superdoc:mainfrom

nick/sd-2736-undoredo-only-work-if-staying-in-same-containersuperdoc-dev/superdoc:nick/sd-2736-undoredo-only-work-if-staying-in-same-containerCopy head branch name to clipboard