Custom bidirectional markdown converter (no new deps) with full round-trip
support for database-view, wikilink, mention nodes. DualEditor component wraps
PageEditor with a toolbar toggle (WYSIWYG<->markdown), lossy-switch modal, and
localStorage persistence per page. 77 tests covering 24 round-trip cases + 4
custom nodes + 9 edge cases. i18n FR+EN.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>