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/app/api/brainstorm/shared/route.ts

@@ -0,0 +1,48 @@
+import { NextResponse } from 'next/server'
+import prisma from '@/lib/prisma'
+import { auth } from '@/auth'
+
+export async function GET() {
+  const session = await auth()
+  if (!session?.user?.id) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  try {
+    const shares = await prisma.brainstormShare.findMany({
+      where: {
+        userId: session.user.id,
+        status: 'accepted',
+      },
+      select: {
+        sessionId: true,
+        permission: true,
+        session: {
+          select: {
+            id: true,
+            seedIdea: true,
+            createdAt: true,
+            updatedAt: true,
+          },
+        },
+      },
+    })
+
+    const data = shares.map((s) => ({
+      id: s.session.id,
+      seedIdea: s.session.seedIdea,
+      sourceNoteId: null,
+      exportedNoteId: null,
+      createdAt: s.session.createdAt,
+      updatedAt: s.session.updatedAt,
+      totalIdeas: 0,
+      activeIdeas: 0,
+      _isShared: true,
+    }))
+
+    return NextResponse.json({ success: true, data })
+  } catch (error) {
+    console.error('Error fetching shared brainstorms:', error)
+    return NextResponse.json({ success: true, data: [] })
+  }
+}