feat(insights): peek panel au clic sur un nœud — slide droite, contenu note

- handleNoteClick fetch la note + ouvre peek panel au lieu de naviguer
- Panel fixed right (left en RTL), spring animation (stiffness 340 damping 34)
- Header avec titre + boutons Maximize2 (ouvrir note complète) et X (fermer)
- Content rendu en read-only via dangerouslySetInnerHTML
- prefers-reduced-motion: animation désactivée
- responsive: w-full sur mobile, 50vw/640px max sur desktop

memento-note/components/sidebar.tsx

@@ -1159,7 +1159,7 @@ export function Sidebar({ className, user }: { className?: string; user?: any })
         className={cn(
           // Mobile: fixed overlay, slide in/out
           'fixed inset-y-0 start-0 z-[70] md:relative md:z-auto',
-          'h-full min-h-0 w-80 shrink-0 flex flex-row overflow-hidden',
+          'h-full min-h-0 w-80 xl:w-[22rem] 2xl:w-[26rem] shrink-0 flex flex-row overflow-hidden',
           'transition-transform duration-300 ease-in-out',
           isMobileOpen ? 'translate-x-0 shadow-2xl' : '-translate-x-full md:translate-x-0',
           'border-e border-border/40 bg-white/95 md:bg-white/30 backdrop-blur-md sidebar-shadow dark:border-white/6 dark:bg-[#151515] dark:backdrop-blur-none',