Make TP the sole owner of live-buffer text-property publication, mount spans, scoped diff execution, and transaction rollback. Ebox now computes layout owners and retained surface plans, publishes handle/viewport/theme/scroll changes through TP, and keeps its mirrored runtime state transactionally consistent. Remove the former Ebox marker/index/patch executor instead of preserving a second mutation path.\n\nVerification:\n- make ci EMACS=/Applications/Emacs.app/Contents/MacOS/Emacs\n- make package-lint-install EMACS=/Applications/Emacs.app/Contents/MacOS/Emacs\n- strict byte compilation passed for 16 files\n- Ebox production has no tp-- private calls or marker writers\n- TP production has no Ebox dependency
Split the verified renderer, layout engine, Grid support, native boundary, tests, examples, and paired documentation into the independent Ebox repository. Keep ETAF and application concerns outside this package.
