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/ai/tools/registry.ts

@@ -52,7 +52,7 @@ class ToolRegistry {
    * When webOnly is true, only web tools are included (no note access).
    */
   buildToolsForChat(ctx: ToolContext & { webOnly?: boolean }): Record<string, any> {
-    const toolNames: string[] = ctx.webOnly ? [] : ['note_search', 'note_read']
+    const toolNames: string[] = ctx.webOnly ? [] : ['note_search', 'note_read', 'document_search', 'task_extract']
 
     // Add web tools only when user toggled web search AND config is present
     if (ctx.webSearch) {