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/dashboard-agent-carousel.tsx

@@ -0,0 +1,158 @@
+'use client'
+
+import { useState } from 'react'
+import { motion, AnimatePresence } from 'motion/react'
+import { Search, Bot, ChevronLeft, ChevronRight, Loader2 } from 'lucide-react'
+import { useLanguage } from '@/lib/i18n'
+import { DashboardWidgetTitleRow } from '@/components/dashboard-widget-title-row'
+
+export interface AgentSuggestion {
+  id: string
+  topic: string
+  reason: string
+  relatedNoteCount: number
+  suggestedFrequency: string
+}
+
+export interface DashboardAgentCarouselProps {
+  suggestions: AgentSuggestion[]
+  loading?: boolean
+  actingId: string | null
+  formatFrequency: (f: string) => string
+  onAccept: (id: string) => void
+  onDismiss: (id: string) => void
+  prefersReducedMotion?: boolean
+}
+
+export function DashboardAgentCarousel({
+  suggestions,
+  loading,
+  actingId,
+  formatFrequency,
+  onAccept,
+  onDismiss,
+  prefersReducedMotion,
+}: DashboardAgentCarouselProps) {
+  const { t } = useLanguage()
+  const [idx, setIdx] = useState(0)
+
+  const navActions = suggestions.length > 1 ? (
+    <div className="flex items-center gap-1">
+      <button
+        type="button"
+        onClick={() => setIdx(i => Math.max(0, i - 1))}
+        disabled={idx === 0}
+        className="p-1 rounded border border-border/30 disabled:opacity-25"
+        aria-label={t('homeDashboard.intelPrev')}
+      >
+        <ChevronLeft size={12} />
+      </button>
+      <span className="text-[8px] font-mono text-concrete px-1">
+        {idx + 1}/{suggestions.length}
+      </span>
+      <button
+        type="button"
+        onClick={() => setIdx(i => Math.min(suggestions.length - 1, i + 1))}
+        disabled={idx >= suggestions.length - 1}
+        className="p-1 rounded border border-border/30 disabled:opacity-25"
+        aria-label={t('homeDashboard.intelNext')}
+      >
+        <ChevronRight size={12} />
+      </button>
+    </div>
+  ) : null
+
+  if (loading) {
+    return <div className="h-[140px] rounded-2xl bg-stone-50 dark:bg-zinc-950/30 animate-pulse" />
+  }
+
+  return (
+    <div className="rounded-2xl border border-border/30 bg-white dark:bg-zinc-900 p-4">
+      <DashboardWidgetTitleRow
+        widgetId="agents"
+        icon={<Bot size={12} className="text-brand-accent" />}
+        title={t('homeDashboard.suggestedResearch')}
+        actions={navActions}
+      />
+
+      {suggestions.length === 0 ? (
+        <p className="text-[11px] text-concrete italic leading-relaxed py-2">
+          {t('homeDashboard.agentsEmpty')}
+        </p>
+      ) : (
+        <AgentSlide
+          current={suggestions[idx]}
+          actingId={actingId}
+          formatFrequency={formatFrequency}
+          onAccept={onAccept}
+          onDismiss={onDismiss}
+          prefersReducedMotion={prefersReducedMotion}
+          t={t}
+        />
+      )}
+    </div>
+  )
+}
+
+function AgentSlide({
+  current,
+  actingId,
+  formatFrequency,
+  onAccept,
+  onDismiss,
+  prefersReducedMotion,
+  t,
+}: {
+  current: AgentSuggestion
+  actingId: string | null
+  formatFrequency: (f: string) => string
+  onAccept: (id: string) => void
+  onDismiss: (id: string) => void
+  prefersReducedMotion?: boolean
+  t: (key: string) => string
+}) {
+  const slide = prefersReducedMotion
+    ? { initial: {}, animate: {}, exit: {} }
+    : { initial: { opacity: 0, y: 8 }, animate: { opacity: 1, y: 0 }, exit: { opacity: 0, y: -8 } }
+
+  return (
+    <AnimatePresence mode="wait">
+      <motion.div
+        key={current.id}
+        initial={slide.initial}
+        animate={slide.animate}
+        exit={slide.exit}
+        transition={{ duration: prefersReducedMotion ? 0 : 0.18 }}
+        className="p-3.5 rounded-xl border border-border/25 bg-stone-50/60 dark:bg-zinc-950/40"
+      >
+        <div className="flex items-start gap-2 mb-2">
+          <Search size={12} className="text-brand-accent shrink-0 mt-0.5" />
+          <p className="text-sm font-semibold text-ink dark:text-dark-ink leading-snug">{current.topic}</p>
+        </div>
+        <p className="text-[11px] text-concrete leading-relaxed line-clamp-2 mb-3">{current.reason}</p>
+        <p className="text-[8px] font-mono uppercase text-concrete mb-3">
+          {current.relatedNoteCount} {t('homeDashboard.notes')} · {formatFrequency(current.suggestedFrequency)}
+        </p>
+        <div className="flex gap-2">
+          <button
+            type="button"
+            disabled={actingId === current.id}
+            onClick={() => onDismiss(current.id)}
+            className="text-[9px] font-mono uppercase px-2.5 py-1.5 rounded-lg border border-border/40 text-concrete hover:text-ink transition-colors disabled:opacity-40"
+          >
+            {t('homeDashboard.dismiss')}
+          </button>
+          <button
+            type="button"
+            disabled={actingId === current.id}
+            onClick={() => onAccept(current.id)}
+            className="flex-1 inline-flex items-center justify-center gap-1 text-[9px] font-mono uppercase px-2.5 py-1.5 rounded-lg bg-ink text-white dark:bg-white dark:text-black font-bold hover:opacity-90 disabled:opacity-40"
+          >
+            {actingId === current.id ? <Loader2 size={10} className="animate-spin" /> : null}
+            {t('homeDashboard.createAgent')}
+          </button>
+        </div>
+      </motion.div>
+    </AnimatePresence>
+  )
+}