feat(dashboard): tableau de bord Second Brain configurable avec chargement progressif

Briefing granulaire, pistes rapides puis enrichissement async, layout persisté v5,
suggestions agents, intégration Gmail et navigation sidebar alignée sur /home.

Co-authored-by: Cursor <cursoragent@cursor.com>

memento-note/context/notebooks-context.tsx

@@ -10,6 +10,7 @@ import { getNoteById } from '@/app/actions/notes'
 import { useNoteRefresh } from './NoteRefreshContext'
 import { toast } from 'sonner'
 import { queryKeys } from '@/lib/query-keys'
+import { useLanguage } from '@/lib/i18n'
 
 // ===== INPUT TYPES =====
 export interface CreateNotebookInput {
@@ -101,6 +102,7 @@ interface NotebooksProviderProps {
 export function NotebooksProvider({ children, initialNotebooks = [] }: NotebooksProviderProps) {
   // ===== BASE STATE =====
   const queryClient = useQueryClient()
+  const { t } = useLanguage()
   const [notebooks, setNotebooks] = useState<Notebook[]>(initialNotebooks)
   const [currentNotebook, setCurrentNotebook] = useState<Notebook | null>(null)
   const [isLoading, setIsLoading] = useState(true)
@@ -401,14 +403,12 @@ export function NotebooksProvider({ children, initialNotebooks = [] }: Notebooks
         emitNoteChange({ type: 'updated', note: movedNote })
       }
     } catch (error) {
-      toast.error('Failed to move note. Please try again.')
+      toast.error(t('notes.moveFailed'))
       throw error
     } finally {
       setIsMovingNote(false)
     }
-  }, [queryClient, triggerNotebooksRefresh])
-
-  // ===== ACTIONS: AI (STUBS) =====
+  }, [queryClient, triggerNotebooksRefresh, t])
   const suggestNotebookForNote = useCallback(async (_noteContent: string) => {
     // Stub pour l'instant - retourne null
     return null