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/components/block-picker.tsx

@@ -3,6 +3,7 @@
 import { useState, useEffect, useMemo } from 'react'
 import { motion, AnimatePresence } from 'framer-motion'
 import { Search, Sparkles, Link2, X, Folder } from 'lucide-react'
+import { useLanguage } from '@/lib/i18n'
 
 export interface BlockSuggestion {
   blockId: string
@@ -22,6 +23,7 @@ interface BlockPickerProps {
 }
 
 export function BlockPicker({ isOpen, onClose, currentNoteId, onSelectBlock }: BlockPickerProps) {
+  const { t } = useLanguage()
   const [activeTab, setActiveTab] = useState<'suggestions' | 'search'>('suggestions')
   const [searchQuery, setSearchQuery] = useState('')
   const [suggestions, setSuggestions] = useState<BlockSuggestion[]>([])
@@ -134,7 +136,7 @@ export function BlockPicker({ isOpen, onClose, currentNoteId, onSelectBlock }: B
                     type="text"
                     value={searchQuery}
                     onChange={e => setSearchQuery(e.target.value)}
-                    placeholder="Rechercher un extrait de note..."
+                    placeholder={t('blockPicker.searchPlaceholder')}
                     className="w-full bg-white dark:bg-zinc-850 border border-[#D5D2CD] dark:border-neutral-800 rounded-xl pl-9 pr-4 py-2 text-xs outline-none focus:border-blue-500 focus:ring-1 focus:ring-blue-500/20 transition-all font-sans"
                     autoFocus
                   />