feat(flashcards): révision SM-2, génération IA et page /revision

Livre US-FLASHCARDS avec decks, session de révision, stats et migration Prisma. Finalise le Web Clipper (i18n 15 langues) et corrige les erreurs ESLint bloquant la CI.

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

memento-note/components/flashcards/revision-heatmap.tsx

@@ -0,0 +1,69 @@
+'use client'
+
+import { useMemo } from 'react'
+import { cn } from '@/lib/utils'
+import { useLanguage } from '@/lib/i18n'
+
+interface HeatmapDay {
+  date: string
+  count: number
+}
+
+interface RevisionHeatmapProps {
+  data: HeatmapDay[]
+  className?: string
+}
+
+function intensityClass(count: number, max: number): string {
+  if (count <= 0) return 'bg-black/[0.04] dark:bg-white/[0.06]'
+  const ratio = count / Math.max(max, 1)
+  if (ratio >= 0.75) return 'bg-brand-accent'
+  if (ratio >= 0.5) return 'bg-brand-accent/70'
+  if (ratio >= 0.25) return 'bg-brand-accent/40'
+  return 'bg-brand-accent/20'
+}
+
+export function RevisionHeatmap({ data, className }: RevisionHeatmapProps) {
+  const { t } = useLanguage()
+
+  const { cells, maxCount } = useMemo(() => {
+    const map = new Map(data.map((d) => [d.date, d.count]))
+    const today = new Date()
+    const cells: { date: string; count: number; label: string }[] = []
+    for (let i = 89; i >= 0; i--) {
+      const d = new Date(today)
+      d.setDate(d.getDate() - i)
+      const key = d.toISOString().slice(0, 10)
+      cells.push({
+        date: key,
+        count: map.get(key) || 0,
+        label: d.toLocaleDateString(undefined, { day: 'numeric', month: 'short' }),
+      })
+    }
+    const maxCount = Math.max(1, ...cells.map((c) => c.count))
+    return { cells, maxCount }
+  }, [data])
+
+  return (
+    <div className={cn('space-y-3', className)}>
+      <div className="flex items-center justify-between">
+        <p className="text-[10px] font-bold uppercase tracking-widest text-concrete">
+          {t('flashcards.heatmapTitle')}
+        </p>
+        <span className="text-[10px] text-concrete/60">{t('flashcards.heatmapLast90')}</span>
+      </div>
+      <div className="grid grid-cols-[repeat(15,minmax(0,1fr))] gap-1 sm:grid-cols-[repeat(18,minmax(0,1fr))]">
+        {cells.map((cell) => (
+          <div
+            key={cell.date}
+            title={`${cell.label}: ${cell.count}`}
+            className={cn(
+              'aspect-square rounded-[3px] transition-colors',
+              intensityClass(cell.count, maxCount),
+            )}
+          />
+        ))}
+      </div>
+    </div>
+  )
+}