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/prisma/schema.prisma

@@ -9,35 +9,40 @@ datasource db {
 }
 
 model User {
-  id                 String              @id @default(cuid())
-  name               String?
-  email              String              @unique
-  emailVerified      DateTime?
-  password           String?
-  role               String              @default("USER")
-  image              String?
-  theme              String              @default("light")
-  resetToken         String?             @unique
-  resetTokenExpiry   DateTime?
-  createdAt          DateTime            @default(now())
-  updatedAt          DateTime            @updatedAt
-  cardSizeMode       String              @default("variable")
-  accounts           Account[]
-  agents             Agent[]
-  aiFeedback         AiFeedback[]
-  canvases           Canvas[]
-  conversations      Conversation[]
-  labels             Label[]
-  memoryEchoInsights MemoryEchoInsight[]
-  notes              Note[]
-  noteHistories      NoteHistory[]
-  sentShares         NoteShare[]         @relation("SentShares")
-  receivedShares     NoteShare[]         @relation("ReceivedShares")
-  notebooks          Notebook[]
-  sessions           Session[]
-  aiSettings         UserAISettings?
-  workflows          Workflow[]
-  notifications      Notification[]
+  id                    String                  @id @default(cuid())
+  name                  String?
+  email                 String                  @unique
+  emailVerified         DateTime?
+  password              String?
+  role                  String                  @default("USER")
+  image                 String?
+  theme                 String                  @default("light")
+  resetToken            String?                 @unique
+  resetTokenExpiry      DateTime?
+  createdAt             DateTime                @default(now())
+  updatedAt             DateTime                @updatedAt
+  cardSizeMode          String                  @default("variable")
+  accounts              Account[]
+  agents                Agent[]
+  aiFeedback            AiFeedback[]
+  brainstormActivities  BrainstormActivity[]
+  brainstormParticipant BrainstormParticipant[]
+  brainstormSessions    BrainstormSession[]
+  canvases              Canvas[]
+  conversations         Conversation[]
+  labels                Label[]
+  memoryEchoInsights    MemoryEchoInsight[]
+  notes                 Note[]
+  noteHistories         NoteHistory[]
+  sentShares            NoteShare[]             @relation("SentShares")
+  receivedShares        NoteShare[]             @relation("ReceivedShares")
+  sentBrainstormShares  BrainstormShare[]       @relation("SentBrainstormShares")
+  receivedBrainstormShares BrainstormShare[]    @relation("ReceivedBrainstormShares")
+  notebooks             Notebook[]
+  notifications         Notification[]
+  sessions              Session[]
+  aiSettings            UserAISettings?
+  workflows             Workflow[]
 }
 
 model Account {
@@ -82,19 +87,19 @@ model Notebook {
   icon          String?
   color         String?
   order         Int
-  parentId      String?
-  trashedAt     DateTime?
   userId        String
   createdAt     DateTime       @default(now())
   updatedAt     DateTime       @updatedAt
+  parentId      String?
+  trashedAt     DateTime?
   agents        Agent[]
   conversations Conversation[]
   labels        Label[]
   notes         Note[]
-  user          User           @relation(fields: [userId], references: [id], onDelete: Cascade)
-  workflows     Workflow[]
   parent        Notebook?      @relation("NotebookTree", fields: [parentId], references: [id], onDelete: Cascade)
   children      Notebook[]     @relation("NotebookTree")
+  user          User           @relation(fields: [userId], references: [id], onDelete: Cascade)
+  workflows     Workflow[]
 
   @@index([userId, order])
   @@index([userId])
@@ -106,11 +111,11 @@ model Label {
   id         String    @id @default(cuid())
   name       String
   color      String    @default("gray")
-  type       String    @default("user")  // "ai" or "user"
   notebookId String?
   userId     String?
   createdAt  DateTime  @default(now())
   updatedAt  DateTime  @updatedAt
+  type       String    @default("user")
   notebook   Notebook? @relation(fields: [notebookId], references: [id], onDelete: Cascade)
   user       User?     @relation(fields: [userId], references: [id], onDelete: Cascade)
   notes      Note[]    @relation("LabelToNote")
@@ -121,51 +126,56 @@ model Label {
 }
 
 model Note {
-  id                  String              @id @default(cuid())
-  title               String?
-  content             String
-  color               String              @default("default")
-  isPinned            Boolean             @default(false)
-  isArchived          Boolean             @default(false)
-  type                String              @default("richtext")
-  dismissedFromRecent Boolean             @default(false)
-  checkItems          String?
-  labels              String?
-  images              String?
+  id                         String                   @id @default(cuid())
+  title                      String?
+  content                    String
+  color                      String                   @default("default")
+  isPinned                   Boolean                  @default(false)
+  isArchived                 Boolean                  @default(false)
+  type                       String                   @default("richtext")
+  dismissedFromRecent        Boolean                  @default(false)
+  checkItems                 String?
+  labels                     String?
+  images                     String?
+  links                      String?
+  reminder                   DateTime?
+  isReminderDone             Boolean                  @default(false)
+  reminderRecurrence         String?
+  reminderLocation           String?
+  isMarkdown                 Boolean                  @default(false)
+  size                       String                   @default("small")
+  sharedWith                 String?
+  userId                     String?
+  order                      Int                      @default(0)
+  notebookId                 String?
+  createdAt                  DateTime                 @default(now())
+  updatedAt                  DateTime                 @updatedAt
+  contentUpdatedAt           DateTime                 @default(now())
+  autoGenerated              Boolean?
+  aiProvider                 String?
+  aiConfidence               Int?
+  language                   String?
+  languageConfidence         Float?
+  lastAiAnalysis             DateTime?
+  trashedAt                  DateTime?
+  historyEnabled             Boolean                  @default(false)
   /// Illustration SVG (sanitized) for editorial feed thumbnail — optional, peut être généré par IA
-  illustrationSvg     String?
-  links               String?
-  reminder            DateTime?
-  isReminderDone      Boolean             @default(false)
-  reminderRecurrence  String?
-  reminderLocation    String?
-  isMarkdown          Boolean             @default(false) // DEPRECATED: use type = 'markdown' instead
-  size                String              @default("small")
-  sharedWith          String?
-  userId              String?
-  order               Int                 @default(0)
-  notebookId          String?
-  createdAt           DateTime            @default(now())
-  updatedAt           DateTime            @updatedAt
-  contentUpdatedAt    DateTime            @default(now())
-  autoGenerated       Boolean?
-  aiProvider          String?
-  aiConfidence        Int?
-  language            String?
-  languageConfidence  Float?
-  lastAiAnalysis      DateTime?
-  trashedAt           DateTime?
-  tsv                 Unsupported("tsvector")?
-  aiFeedback          AiFeedback[]
-  memoryEchoAsNote1   MemoryEchoInsight[] @relation("EchoNote1")
-  memoryEchoAsNote2   MemoryEchoInsight[] @relation("EchoNote2")
-  notebook            Notebook?           @relation(fields: [notebookId], references: [id])
-  user                User?               @relation(fields: [userId], references: [id], onDelete: Cascade)
-  noteEmbedding       NoteEmbedding?
-  shares              NoteShare[]
-  labelRelations      Label[]             @relation("LabelToNote")
-  historyEntries      NoteHistory[]
-  historyEnabled      Boolean         @default(false)
+  illustrationSvg            String?
+  tsv                        Unsupported("tsvector")?
+  aiFeedback                 AiFeedback[]
+  convertedBrainstormIdeas   BrainstormIdea[]         @relation("ConvertedBrainstormIdea")
+  exportedBrainstormSessions BrainstormSession[]      @relation("ExportedBrainstorm")
+  sourceBrainstormSessions   BrainstormSession[]      @relation("SourceBrainstorm")
+  memoryEchoAsNote1          MemoryEchoInsight[]      @relation("EchoNote1")
+  memoryEchoAsNote2          MemoryEchoInsight[]      @relation("EchoNote2")
+  notebook                   Notebook?                @relation(fields: [notebookId], references: [id])
+  user                       User?                    @relation(fields: [userId], references: [id], onDelete: Cascade)
+  noteEmbedding              NoteEmbedding?
+  historyEntries             NoteHistory[]
+  shares                     NoteShare[]
+  labelRelations             Label[]                  @relation("LabelToNote")
+  attachments                NoteAttachment[]
+  brainstormNoteRefs         BrainstormNoteRef[]
 
   @@index([isPinned])
   @@index([isArchived])
@@ -178,26 +188,26 @@ model Note {
 
 model NoteHistory {
   id         String   @id @default(cuid())
-  noteId      String
-  userId      String
-  version     Int
-  reason      String?
-  title       String?
-  content     String
-  color       String
-  isPinned    Boolean
-  isArchived  Boolean
-  type        String
-  checkItems  String?
-  labels      String?
-  images      String?
-  links       String?
-  isMarkdown  Boolean
-  size        String
-  notebookId  String?
-  createdAt   DateTime @default(now())
-  note        Note     @relation(fields: [noteId], references: [id], onDelete: Cascade)
-  user        User     @relation(fields: [userId], references: [id], onDelete: Cascade)
+  noteId     String
+  userId     String
+  version    Int
+  reason     String?
+  title      String?
+  content    String
+  color      String
+  isPinned   Boolean
+  isArchived Boolean
+  type       String
+  checkItems String?
+  labels     String?
+  images     String?
+  links      String?
+  isMarkdown Boolean
+  size       String
+  notebookId String?
+  createdAt  DateTime @default(now())
+  note       Note     @relation(fields: [noteId], references: [id], onDelete: Cascade)
+  user       User     @relation(fields: [userId], references: [id], onDelete: Cascade)
 
   @@unique([noteId, version])
   @@index([noteId, createdAt(sort: Desc)])
@@ -284,10 +294,10 @@ model UserAISettings {
   desktopNotifications Boolean @default(false)
   anonymousAnalytics   Boolean @default(false)
   autoLabeling         Boolean @default(true)
+  fontFamily           String  @default("inter")
+  languageDetection    Boolean @default(true)
   noteHistory          Boolean @default(false)
   noteHistoryMode      String  @default("manual")
-  languageDetection    Boolean @default(true)
-  fontFamily           String  @default("inter")
   autoSave             Boolean @default(true)
   user                 User    @relation(fields: [userId], references: [id], onDelete: Cascade)
 
@@ -300,9 +310,8 @@ model UserAISettings {
 model NoteEmbedding {
   id        String   @id @default(cuid())
   noteId    String   @unique
-  embedding Unsupported("vector(1536)")
+  embedding String
   createdAt DateTime @default(now())
-  updatedAt DateTime @default(now()) @updatedAt
   note      Note     @relation(fields: [noteId], references: [id], onDelete: Cascade)
 
   @@index([noteId])
@@ -321,9 +330,6 @@ model Agent {
   isEnabled        Boolean       @default(true)
   targetNotebookId String?
   sourceNotebookId String?
-  sourceNoteIds    String?
-  slideTheme       String?
-  slideStyle       String?
   tools            String?       @default("[]")
   maxSteps         Int           @default(10)
   notifyEmail      Boolean       @default(false)
@@ -334,6 +340,9 @@ model Agent {
   scheduledTime    String?       @default("08:00")
   scheduledDay     Int?
   timezone         String?
+  sourceNoteIds    String?
+  slideStyle       String?
+  slideTheme       String?
   notebook         Notebook?     @relation(fields: [targetNotebookId], references: [id])
   user             User          @relation(fields: [userId], references: [id], onDelete: Cascade)
   actions          AgentAction[]
@@ -426,17 +435,198 @@ model WorkflowRun {
 }
 
 model Notification {
-  id         String   @id @default(cuid())
-  userId     String
-  type       String   // "agent_success", "agent_failure", "share", "reminder", "system"
-  title      String
-  message    String?
-  read       Boolean  @default(false)
-  actionUrl  String?  // e.g. "/agents" or "/notes/xxx"
-  relatedId  String?  // e.g. agentId or noteId
-  createdAt  DateTime @default(now())
-  user       User     @relation(fields: [userId], references: [id], onDelete: Cascade)
+  id        String   @id @default(cuid())
+  userId    String
+  type      String
+  title     String
+  message   String?
+  read      Boolean  @default(false)
+  actionUrl String?
+  relatedId String?
+  createdAt DateTime @default(now())
+  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)
 
   @@index([userId, read])
   @@index([userId, createdAt])
 }
+
+model BrainstormSession {
+  id               String    @id @default(cuid())
+  seedIdea         String
+  sourceNoteId     String?
+  contextNoteIds   String?
+  exportedNoteId   String?
+  userId           String
+  inviteToken      String?   @unique
+  inviteExpiry     DateTime?
+  liveblocksRoomId String?
+  isPublic         Boolean   @default(false)
+  guestCanEdit     Boolean   @default(false)
+  status           String    @default("active")
+  createdAt        DateTime  @default(now())
+  updatedAt        DateTime  @updatedAt
+  ideas            BrainstormIdea[]
+  participants     BrainstormParticipant[]
+  activities       BrainstormActivity[]
+  shares           BrainstormShare[]
+  snapshots        BrainstormSnapshot[]
+  sourceNote       Note?     @relation("SourceBrainstorm", fields: [sourceNoteId], references: [id])
+  exportedNote     Note?     @relation("ExportedBrainstorm", fields: [exportedNoteId], references: [id])
+  user             User      @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@index([userId])
+  @@index([userId, createdAt])
+  @@index([inviteToken])
+  @@index([isPublic])
+}
+
+model BrainstormIdea {
+  id                String              @id @default(cuid())
+  sessionId         String
+  waveNumber        Int
+  title             String
+  description       String
+  connectionToSeed  String?
+  noveltyScore      Int?
+  parentIdeaId      String?
+  convertedToNoteId String?
+  relatedNoteIds    String?
+  status            String              @default("active")
+  positionX         Float?
+  positionY         Float?
+  createdAt         DateTime            @default(now())
+  createdBy         String?
+  createdByType     String?             @default("ai")
+  convertedNote     Note?               @relation("ConvertedBrainstormIdea", fields: [convertedToNoteId], references: [id])
+  parentIdea        BrainstormIdea?     @relation("IdeaTree", fields: [parentIdeaId], references: [id])
+  children          BrainstormIdea[]    @relation("IdeaTree")
+  session           BrainstormSession   @relation(fields: [sessionId], references: [id], onDelete: Cascade)
+  noteRefs          BrainstormNoteRef[]
+
+  @@index([sessionId])
+  @@index([waveNumber])
+  @@index([status])
+  @@index([parentIdeaId])
+  @@index([sessionId, status])
+  @@index([sessionId, waveNumber, createdAt])
+}
+
+model BrainstormNoteRef {
+  id          String         @id @default(cuid())
+  ideaId      String
+  noteId      String?
+  relation    String
+  explanation String
+  verdict     String         @default("unresolved")
+  createdAt   DateTime       @default(now())
+  visibility  String         @default("participants")
+  idea        BrainstormIdea @relation(fields: [ideaId], references: [id], onDelete: Cascade)
+  note        Note?          @relation(fields: [noteId], references: [id])
+
+  @@index([ideaId])
+  @@index([noteId])
+  @@index([noteId, relation])
+  @@index([visibility])
+}
+
+model BrainstormParticipant {
+  id         String            @id @default(cuid())
+  sessionId  String
+  userId     String
+  role       String            @default("viewer")
+  joinedAt   DateTime          @default(now())
+  lastSeenAt DateTime          @default(now())
+  session    BrainstormSession @relation(fields: [sessionId], references: [id], onDelete: Cascade)
+  user       User              @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@unique([sessionId, userId])
+  @@index([sessionId])
+  @@index([userId])
+  @@index([sessionId, userId, role])
+}
+
+model BrainstormActivity {
+  id        String            @id @default(cuid())
+  sessionId String
+  userId    String?
+  action    String
+  details   String?
+  createdAt DateTime          @default(now())
+  session   BrainstormSession @relation(fields: [sessionId], references: [id], onDelete: Cascade)
+  user      User?             @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@index([sessionId, createdAt], map: "BrainstormActivity_sessionId_createdAt_asc_idx")
+  @@index([sessionId, createdAt(sort: Desc)], map: "BrainstormActivity_sessionId_createdAt_desc_idx")
+  @@index([sessionId, createdAt])
+}
+
+model BrainstormShare {
+  id          String    @id @default(cuid())
+  sessionId   String
+  userId      String
+  sharedBy    String
+  status      String    @default("pending")
+  permission  String    @default("editor")
+  notifiedAt  DateTime?
+  respondedAt DateTime?
+  createdAt   DateTime  @default(now())
+  updatedAt   DateTime  @updatedAt
+  session     BrainstormSession @relation(fields: [sessionId], references: [id], onDelete: Cascade)
+  sharer      User              @relation("SentBrainstormShares", fields: [sharedBy], references: [id], onDelete: Cascade)
+  user        User              @relation("ReceivedBrainstormShares", fields: [userId], references: [id], onDelete: Cascade)
+
+  @@unique([sessionId, userId])
+  @@index([userId])
+  @@index([status])
+}
+
+model BrainstormSnapshot {
+  id          String   @id @default(cuid())
+  sessionId   String
+  activityId  String?
+  step        Int
+  label       String?
+  ideaGraph   String
+  createdAt   DateTime @default(now())
+  session     BrainstormSession @relation(fields: [sessionId], references: [id], onDelete: Cascade)
+
+  @@index([sessionId, step])
+  @@index([sessionId, createdAt])
+  @@index([activityId])
+}
+
+model NoteAttachment {
+  id          String   @id @default(cuid())
+  noteId      String
+  fileName    String
+  fileType    String
+  fileSize    Int
+  filePath    String
+  mimeType    String
+  status      String   @default("pending")
+  pageCount   Int?
+  error       String?
+  createdAt   DateTime @default(now())
+  updatedAt   DateTime @updatedAt
+  note        Note     @relation(fields: [noteId], references: [id], onDelete: Cascade)
+  chunks      DocumentChunk[]
+
+  @@index([noteId])
+  @@index([status])
+}
+
+model DocumentChunk {
+  id           String   @id @default(cuid())
+  attachmentId String
+  content      String
+  chunkIndex   Int
+  pageNumber   Int?
+  startChar    Int?
+  endChar      Int?
+  metadata     String?
+  createdAt    DateTime @default(now())
+  attachment   NoteAttachment @relation(fields: [attachmentId], references: [id], onDelete: Cascade)
+
+  @@index([attachmentId])
+  @@index([attachmentId, chunkIndex])
+}