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/app/api/flashcards/generate/route.ts

@@ -0,0 +1,81 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { auth } from '@/auth'
+import prisma from '@/lib/prisma'
+import { getAISettings } from '@/app/actions/ai-settings'
+import { checkEntitlementOrThrow, QuotaExceededError, incrementUsageAsync } from '@/lib/entitlements'
+import { hasUserAiConsent } from '@/lib/consent/server-consent'
+import { generateFlashcardsFromNote, type FlashcardStyle } from '@/lib/flashcards/generate-flashcards'
+import { stripHtmlToText } from '@/lib/flashcards/deck-utils'
+
+export async function POST(request: NextRequest) {
+  try {
+    const session = await auth()
+    if (!session?.user?.id) {
+      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+    }
+
+    if (!(await hasUserAiConsent())) {
+      return NextResponse.json({ error: 'ai_consent_required' }, { status: 403 })
+    }
+
+    const userSettings = await getAISettings(session.user.id)
+    if (userSettings.paragraphRefactor === false) {
+      return NextResponse.json({ error: 'Feature disabled' }, { status: 403 })
+    }
+
+    const body = await request.json()
+    const noteId = typeof body.noteId === 'string' ? body.noteId : ''
+    const count = typeof body.count === 'number' ? body.count : 10
+    const styleRaw = typeof body.style === 'string' ? body.style : 'qa'
+    const style: FlashcardStyle = ['qa', 'cloze', 'concept'].includes(styleRaw)
+      ? (styleRaw as FlashcardStyle)
+      : 'qa'
+
+    if (!noteId) {
+      return NextResponse.json({ error: 'noteId required' }, { status: 400 })
+    }
+
+    const note = await prisma.note.findFirst({
+      where: { id: noteId, userId: session.user.id, trashedAt: null },
+      select: { id: true, title: true, content: true, language: true },
+    })
+    if (!note) {
+      return NextResponse.json({ error: 'Note not found' }, { status: 404 })
+    }
+
+    const textContent = stripHtmlToText(note.content)
+    if (textContent.length < 80) {
+      return NextResponse.json({ error: 'Not enough content to generate flashcards' }, { status: 400 })
+    }
+
+    try {
+      await checkEntitlementOrThrow(session.user.id, 'reformulate')
+    } catch (err) {
+      if (err instanceof QuotaExceededError) {
+        const isTierLocked = err.currentQuota === 0
+        return NextResponse.json({
+          error: isTierLocked ? 'feature_locked' : 'quota_exceeded',
+          errorKey: isTierLocked ? 'ai.featureLocked' : 'ai.quotaExceeded',
+          quotaExceeded: true,
+        }, { status: 402 })
+      }
+      throw err
+    }
+
+    const cards = await generateFlashcardsFromNote({
+      title: note.title || 'Untitled',
+      textContent,
+      count,
+      style,
+      language: note.language || undefined,
+    })
+
+    incrementUsageAsync(session.user.id, 'reformulate')
+
+    return NextResponse.json({ cards, noteId: note.id, style })
+  } catch (error) {
+    console.error('[flashcards/generate]', error)
+    const message = error instanceof Error ? error.message : 'Generation failed'
+    return NextResponse.json({ error: message }, { status: 500 })
+  }
+}