feat(ui): panneau repliable, carnets plus lisibles et accueil plus clair

Harmonise la liste des notes et l’éditeur (titres, dates, retour),
rend la saisie rapide et les raccourcis de l’accueil utilisables
sur téléphone, et conserve le panneau latéral repliable.

memento-note/app/(main)/layout.tsx

@@ -7,6 +7,7 @@ import { detectUserLanguage, parseAcceptLanguage } from "@/lib/i18n/detect-user-
 import { loadTranslations } from "@/lib/i18n/load-translations";
 import { getAISettings } from "@/app/actions/ai-settings";
 import { AIChatLayoutBridge } from "@/components/ai-chat-layout-bridge";
+import { MobileNavigationBar } from "@/components/mobile-navigation-bar";
 
 
 export default async function MainLayout({
@@ -42,6 +43,7 @@ export default async function MainLayout({
         </Suspense>
 
         <main className="flex min-h-0 flex-1 flex-col overflow-y-auto scroll-smooth bg-background" id="main-content">
+          <MobileNavigationBar />
           <a href="#main-content" className="sr-only focus:not-sr-only focus:absolute focus:z-[9999] focus:top-2 focus:left-2 focus:bg-brand-accent focus:text-white focus:px-4 focus:py-2 focus:rounded-lg focus:text-sm focus:font-bold">
             Skip to content
           </a>
@@ -53,4 +55,3 @@ export default async function MainLayout({
     </ProvidersWrapper>
   );
 }
-