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/components/brainstorm/brainstorm-create-dialog.tsx

@@ -0,0 +1,84 @@
+'use client'
+
+import React, { useState } from 'react'
+import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog'
+import { Button } from '@/components/ui/button'
+import { Sparkles } from 'lucide-react'
+import { useLanguage } from '@/lib/i18n'
+
+interface BrainstormCreateDialogProps {
+  open: boolean
+  onOpenChange: (open: boolean) => void
+  onSubmit: (seedIdea: string) => void
+  isLoading?: boolean
+}
+
+export function BrainstormCreateDialog({
+  open,
+  onOpenChange,
+  onSubmit,
+  isLoading,
+}: BrainstormCreateDialogProps) {
+  const { t } = useLanguage()
+  const [seedIdea, setSeedIdea] = useState('')
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault()
+    if (!seedIdea.trim()) return
+    onSubmit(seedIdea.trim())
+    setSeedIdea('')
+  }
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent className="sm:max-w-md bg-white dark:bg-zinc-900 border-border">
+        <DialogHeader>
+          <DialogTitle className="flex items-center gap-2">
+            <Sparkles size={18} className="text-orange-500" />
+            {t('brainstorm.newBrainstorm')}
+          </DialogTitle>
+        </DialogHeader>
+        <form onSubmit={handleSubmit} className="space-y-4">
+          <div>
+            <label className="text-xs text-muted-foreground uppercase tracking-wider mb-1 block">
+              {t('brainstorm.seedLabel')}
+            </label>
+            <textarea
+              value={seedIdea}
+              onChange={(e) => setSeedIdea(e.target.value)}
+              placeholder={t('brainstorm.ideaPromptDetailed')}
+              className="w-full h-28 px-3 py-2 text-sm border border-border rounded-lg bg-transparent focus:outline-none focus:ring-2 focus:ring-orange-500/30 resize-none"
+              autoFocus
+            />
+          </div>
+          <div className="flex justify-end gap-2">
+            <Button
+              type="button"
+              variant="outline"
+              onClick={() => onOpenChange(false)}
+            >
+              {t('brainstorm.cancel')}
+            </Button>
+            <Button
+              type="submit"
+              disabled={!seedIdea.trim() || isLoading}
+              className="bg-orange-600 hover:bg-orange-700 text-white"
+            >
+              {isLoading ? (
+                <>
+                  <Sparkles size={14} className="mr-1 animate-spin" />
+                  {t('brainstorm.generating')}
+                </>
+              ) : (
+                <>
+                  <Sparkles size={14} className="mr-1" />
+                  {t('brainstorm.startBrainstorm')}
+                </>
+              )}
+            </Button>
+          </div>
+        </form>
+      </DialogContent>
+    </Dialog>
+  )
+}