fix(editeur): #93 garde-fous de session d'edition inline (onglets, ecriture externe) + hooks de versionnage documentes

Une session d'edition inline (Editer/Forge) qui possede la zone de contenu etait detruite par deux chemins qui vident cette zone : activation d'onglet (TabManager.activate, PaneTabManager.activate) -> detachInlineEditor() avant le placeholder ; evenement SSE index_updated -> reloadExternalWrite() recharge le tampon de l'editeur au lieu de re-rendre la vue lecture. Nouveau helper queryEditor() ; closeEditor() remet le conteneur dans la modale avant de restaurer en-tete/pied/marque. docs/CONTRIBUTING.md documente scripts/install-hooks.sh.

frontend/js/editor-inline.js

@@ -69,6 +69,17 @@ export function isInlineEditorActive() {
   return !!(container && container.classList.contains(INLINE_CONTAINER_CLASS));
 }
 
+/**
+ * Query an element inside the editor container, wherever it currently lives
+ * (modal or content area). Use it instead of `modal.querySelector(...)` for the
+ * header/footer/brand, which move with the container in inline mode (#93).
+ */
+export function queryEditor(selector) {
+  const container = getEditorContainer();
+  const scope = container || getEditorModal();
+  return scope ? scope.querySelector(selector) : null;
+}
+
 /**
  * Move the editor container into `area`, replacing the rendered document.
  * @returns {boolean} true when the container was mounted inline.