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

.claude/settings.json

@@ -4,7 +4,8 @@
       "Bash(npm run *)",
       "Bash(curl -s http://localhost:3000)",
       "Bash(curl -s -o /dev/null -w \"%{http_code}\" http://localhost:3000/)",
-      "Bash(kill 3309513)"
+      "Bash(kill 3309513)",
+      "Bash(python3 /home/devparsa/dev/Momento/_bmad/scripts/resolve_customization.py --skill /home/devparsa/dev/Momento/.claude/skills/bmad-create-architecture --key workflow)"
     ]
   }
 }