fix: exercices dans menu GraduationCap + équations KaTeX + refresh liste

- Menu déroulant GraduationCap : Flashcards + Exercices réunis
- Fix: language non défini dans toolbar (useLanguage destructuring)
- Fix: équations 658071 → KaTeX dans exercices (preprocessMathInHtml partagé)
- lib/text/math-preprocess.ts : utilitaire partagé wizard + exercices
- Toast avec bouton 'Voir' pour rafraîchir après création exercices
- emitNoteChange pour rafraîchir la liste
- i18n FR/EN

memento-note/tests/unit/chunk-indexing.test.ts

@@ -1,132 +0,0 @@
-import { test, expect, describe, beforeAll, afterAll, beforeEach } from 'vitest'
-import { prisma } from '../../lib/prisma'
-import { ChunkIndexingService } from '../../lib/ai/services/chunk-indexing.service'
-import { embeddingService } from '../../lib/ai/services/embedding.service'
-import crypto from 'crypto'
-
-const testNoteId = 'test-chunk-000001'
-
-describe('US-CHUNK-2 : Indexation incrémentale avec dedup', () => {
-  let originalEmbedText: any
-
-  beforeAll(async () => {
-    originalEmbedText = embeddingService.embedText
-    embeddingService.embedText = async (text: string) => {
-      const hash = crypto.createHash('md5').update(text).digest()
-      return Array.from({ length: 1536 }, (_, i) => hash[i % 16] / 255)
-    }
-
-    await prisma.note.upsert({
-      where: { id: testNoteId },
-      create: {
-        id: testNoteId,
-        title: 'Test Note for Chunk Indexing',
-        content: '<p>Test</p>',
-      },
-      update: {},
-    })
-  })
-
-  afterAll(async () => {
-    embeddingService.embedText = originalEmbedText
-    await prisma.noteEmbeddingChunk.deleteMany({ where: { noteId: testNoteId } })
-    await prisma.note.delete({ where: { id: testNoteId } }).catch(() => {})
-  })
-
-  beforeEach(async () => {
-    await prisma.noteEmbeddingChunk.deleteMany({ where: { noteId: testNoteId } })
-  })
-
-  const longContent = Array.from({ length: 8 }, (_, i) =>
-    `Section ${i} de la note de test. `.repeat(60).trim(),
-  ).join('\n\n')
-
-  test('première indexation → tous les fragments sont nouveaux', async () => {
-    const service = new ChunkIndexingService()
-    const result = await service.indexNote(testNoteId, 'Note de test', longContent)
-
-    expect(result.newFragments).toBeGreaterThan(0)
-    expect(result.deleted).toBe(0)
-    expect(result.skipped).toBe(0)
-  })
-
-  test('deuxième indexation (même contenu) → tout skipped, 0 nouveau', async () => {
-    const service = new ChunkIndexingService()
-    await service.indexNote(testNoteId, 'Note de test', longContent)
-    const result = await service.indexNote(testNoteId, 'Note de test', longContent)
-
-    expect(result.newFragments).toBe(0)
-    expect(result.skipped).toBeGreaterThan(0)
-    expect(result.deleted).toBe(0)
-  })
-
-  test('modification d\'une section → 1 nouveau, reste skip', async () => {
-    const service = new ChunkIndexingService()
-    await service.indexNote(testNoteId, 'Note de test', longContent)
-
-    const sections = Array.from({ length: 8 }, (_, i) =>
-      `Section ${i === 3 ? 'MODIFIÉE' : i} de la note de test. `.repeat(60).trim(),
-    )
-    const modified = sections.join('\n\n')
-
-    const result = await service.indexNote(testNoteId, 'Note de test', modified)
-
-    expect(result.newFragments).toBeGreaterThanOrEqual(1)
-    expect(result.deleted).toBeGreaterThanOrEqual(1)
-  })
-
-  test('suppression d\'une section → fragments stale nettoyés', async () => {
-    const service = new ChunkIndexingService()
-    const sections = Array.from({ length: 8 }, (_, i) =>
-      `Section ${i} de la note de test. `.repeat(60).trim(),
-    )
-    await service.indexNote(testNoteId, 'Note de test', sections.join('\n\n'))
-
-    const beforeCount = await prisma.noteEmbeddingChunk.count({
-      where: { noteId: testNoteId },
-    })
-
-    const shorter = sections.slice(0, 4).join('\n\n')
-    const result = await service.indexNote(testNoteId, 'Note de test', shorter)
-
-    const afterCount = await prisma.noteEmbeddingChunk.count({
-      where: { noteId: testNoteId },
-    })
-
-    expect(afterCount).toBeLessThan(beforeCount)
-    expect(result.deleted).toBeGreaterThan(0)
-  })
-
-  test('note vide → tous les fragments supprimés', async () => {
-    const service = new ChunkIndexingService()
-    await service.indexNote(testNoteId, 'Note de test', longContent)
-    const result = await service.indexNote(testNoteId, '', '')
-
-    const count = await prisma.noteEmbeddingChunk.count({
-      where: { noteId: testNoteId },
-    })
-
-    expect(count).toBe(0)
-  })
-
-  test('deleteNoteChunks → supprime tout', async () => {
-    const service = new ChunkIndexingService()
-    await service.indexNote(testNoteId, 'Note de test', longContent)
-    await service.deleteNoteChunks(testNoteId)
-
-    const count = await prisma.noteEmbeddingChunk.count({
-      where: { noteId: testNoteId },
-    })
-    expect(count).toBe(0)
-  })
-
-  test('hasChunks → détection correcte', async () => {
-    const service = new ChunkIndexingService()
-    const before = await service.hasChunks(testNoteId)
-    expect(before).toBe(false)
-
-    await service.indexNote(testNoteId, 'Note de test', longContent)
-    const after = await service.hasChunks(testNoteId)
-    expect(after).toBe(true)
-  })
-})