feat: brainstorm sessions, PDF document Q&A, embedding fixes, and UI improvements

- Add brainstorm feature with collaborative canvas, AI idea generation, live cursors, playback, and export
- Add PDF upload/extraction/ingestion pipeline with pgvector document search (RAG)
- Add document Q&A overlay with streaming chat and PDF preview
- Add note attachments UI with status polling, grid layout, and auto-scroll
- Add task extraction AI tool and agent executor improvements
- Fix NoteEmbedding missing updatedAt column, re-index 66 notes with 1536-dim embeddings
- Fix brainstorm 'Create Note' button: add success toast and redirect to created note
- Fix memory echo notification infinite polling
- Fix chat route to always include document_search tool
- Add brainstorm i18n keys across all 14 locales
- Add socket server for real-time brainstorm collaboration
- Add hierarchical notebook selector and organize notebook dialog improvements
- Add sidebar brainstorm section with session management
- Update prisma schema with brainstorm tables, attachments, and document chunks

memento-note/lib/brainstorm-collab.ts

@@ -0,0 +1,130 @@
+import prisma from '@/lib/prisma'
+
+export async function verifyParticipant(
+  sessionId: string,
+  userId: string,
+  requiredRole?: 'host' | 'editor' | 'viewer'
+): Promise<{ isParticipant: boolean; role: string }> {
+  const participant = await prisma.brainstormParticipant.findFirst({
+    where: { sessionId, userId },
+  })
+
+  if (!participant) {
+    return { isParticipant: false, role: 'none' }
+  }
+
+  await prisma.brainstormParticipant.update({
+    where: { id: participant.id },
+    data: { lastSeenAt: new Date() },
+  })
+
+  if (requiredRole === 'host' && participant.role !== 'host') {
+    return { isParticipant: false, role: participant.role }
+  }
+  if (requiredRole === 'editor' && participant.role === 'viewer') {
+    return { isParticipant: false, role: participant.role }
+  }
+
+  return { isParticipant: true, role: participant.role }
+}
+
+export async function logActivity(
+  sessionId: string,
+  action: string,
+  userId?: string | null,
+  details?: Record<string, any>
+) {
+  await prisma.brainstormActivity.create({
+    data: {
+      sessionId,
+      userId: userId || null,
+      action,
+      details: details ? JSON.stringify(details) : null,
+    },
+  })
+}
+
+// [UPDATE - SÉCURITÉ] Résoudre l'userId et le périmètre de notes autorisé pour les appels IA.
+// - Hôte : accès complet à ses notes (publicNoteIds = null)
+// - Invité : restreint aux contextNoteIds publics de la session (publicNoteIds = string[] | [])
+export async function resolveAiContextUserId(
+  sessionId: string,
+  requestingUserId: string
+): Promise<{ aiUserId: string; isGuest: boolean; publicNoteIds: string[] | null }> {
+  const session = await prisma.brainstormSession.findUnique({
+    where: { id: sessionId },
+    select: {
+      userId: true,
+      contextNoteIds: true,
+    },
+  })
+
+  if (!session) throw new Error('Session not found')
+
+  const isHost = session.userId === requestingUserId
+  if (isHost) {
+    return { aiUserId: requestingUserId, isGuest: false, publicNoteIds: null }
+  }
+
+  // Invité : on restreint aux contextNoteIds déclarés publics par l'hôte
+  const publicNoteIds: string[] = session.contextNoteIds
+    ? (JSON.parse(session.contextNoteIds) as string[])
+    : []
+
+  return {
+    aiUserId: session.userId,
+    isGuest: true,
+    publicNoteIds: publicNoteIds.length > 0 ? publicNoteIds : [],
+  }
+}
+
+// [UPDATE - SÉCURITÉ] Sanitize les notes injectées dans un prompt IA pour un invité.
+// Tronque le contenu et masque les entités nommées (Prénom Nom) avec [Person].
+export function sanitizeNotesForGuest(
+  notes: { id: string; title: string | null; summary: string }[]
+): { id: string; title: string; summary: string }[] {
+  const namedEntityRe = /\b[A-ZÀ-Ü][a-zà-ü]+ [A-ZÀ-Ü][a-zà-ü]+\b/g
+  return notes.map(n => ({
+    id: n.id,
+    title: (n.title || 'Note').replace(namedEntityRe, '[Person]'),
+    summary: n.summary.slice(0, 80).replace(namedEntityRe, '[Person]') + '…',
+  }))
+}
+
+export async function captureSnapshot(
+  sessionId: string,
+  label: string,
+  activityId?: string
+): Promise<void> {
+  const ideas = await prisma.brainstormIdea.findMany({
+    where: { sessionId, status: 'active' },
+    select: {
+      id: true,
+      title: true,
+      waveNumber: true,
+      positionX: true,
+      positionY: true,
+      parentIdeaId: true,
+      noveltyScore: true,
+      createdByType: true,
+      status: true,
+    },
+    orderBy: [{ waveNumber: 'asc' }, { createdAt: 'asc' }],
+  })
+
+  const maxStep = await prisma.brainstormSnapshot.findFirst({
+    where: { sessionId },
+    orderBy: { step: 'desc' },
+    select: { step: true },
+  })
+
+  await prisma.brainstormSnapshot.create({
+    data: {
+      sessionId,
+      activityId: activityId || null,
+      step: (maxStep?.step || 0) + 1,
+      label,
+      ideaGraph: JSON.stringify(ideas),
+    },
+  })
+}