fix(brainstorm): dialog sélection carnet sur Create Note depuis canvas

Vrai fix UX: quand l'utilisateur clique 'Create Note' dans le canvas brainstorm,
il voit maintenant un dialog (ConvertNotebookDialog) qui demande dans
quel carnet sauvegarder la note — au lieu d'aller silencieusement dans
le carnet source ou un carnet auto-créé.

- convert-notebook-dialog.tsx (162 lignes): dialog de sélection carnet
  - design system respecté: emerald, memento-paper, font-memento-serif
  - preview de l'idée en card
  - dropdown carnet avec animation d'expansion
  - bouton 'Create note' avec loader
  - role=dialog, aria-modal, aria-label
- brainstorm-page.tsx: convertConfirm state + bouton 'Create Note' ouvre le dialog
- 3 nouvelles clés i18n (EN/FR): convertTitle, convertSubtitle, ideaLabel

.cursor/hooks/state/continual-learning.json

@@ -1,8 +1,8 @@
 {
   "version": 1,
   "lastRunAtMs": 1783196565768,
-  "turnsSinceLastRun": 5,
+  "turnsSinceLastRun": 6,
   "lastTranscriptMtimeMs": 1783196565691.0437,
-  "lastProcessedGenerationId": "7ac52bd5-5714-460a-9c3b-e4b21907d6d7",
+  "lastProcessedGenerationId": "6ccc52d1-8073-4386-b4d0-84c60a305da2",
   "trialStartedAtMs": null
 }

memento-note/components/brainstorm/brainstorm-page.tsx

@@ -54,6 +54,7 @@ import {
 import { useBrainstormSocket } from '@/hooks/use-brainstorm-socket'
 import { LiveCursors, PresenceAvatars, useCursorTracking } from '@/components/brainstorm/live-cursors'
 import { ActivityFeed } from '@/components/brainstorm/activity-feed'
+import { ConvertNotebookDialog } from './convert-notebook-dialog'
 import { BrainstormShareDialog } from '@/components/brainstorm/brainstorm-share-dialog'
 import { GhostCursor } from '@/components/brainstorm/ghost-cursor'
 import { PlaybackBar } from '@/components/brainstorm/playback-bar'
@@ -129,6 +130,7 @@ export function BrainstormPage() {
   const expandIdea = useExpandIdea(activeSessionId || '')
   const dismissIdea = useDismissIdea(activeSessionId || '')
   const convertIdea = useConvertIdea(activeSessionId || '')
+  const [convertConfirm, setConvertConfirm] = useState<BrainstormIdea | null>(null)
   const exportBrainstorm = useExportBrainstorm(activeSessionId || '')
   const finalizeBrainstorm = useFinalizeBrainstorm(activeSessionId || '')
   const deleteBrainstorm = useDeleteBrainstorm()
@@ -896,7 +898,7 @@ export function BrainstormPage() {
                         </span>
                       </button>
                       <button
-                        onClick={() => handleConvert(selectedIdea)}
+                        onClick={() => setConvertConfirm(selectedIdea)}
                         disabled={selectedIdea.status === 'converted' || convertIdea.isPending}
                         className="flex flex-col items-center justify-center p-6 border-2 border-dashed border-border rounded-2xl hover:border-emerald-400/40 hover:bg-emerald-500/5 transition-all group disabled:opacity-50"
                       >
@@ -1156,6 +1158,20 @@ export function BrainstormPage() {
         onClose={peek.close}
         onOpenFully={(n) => { router.push(`/home?openNote=${n.id}`); peek.close() }}
       />
+
+      {/* Dialog de sélection de carnet pour la conversion */}
+      <ConvertNotebookDialog
+        open={convertConfirm !== null}
+        idea={convertConfirm}
+        notebooks={notebooks}
+        defaultNotebookId={urlNotebookId}
+        onClose={() => setConvertConfirm(null)}
+        onConfirm={(notebookId) => {
+          if (!convertConfirm) return
+          handleConvert(convertConfirm, notebookId)
+          setConvertConfirm(null)
+        }}
+      />
     </div>
   )
 }

memento-note/locales/en.json

@@ -3077,7 +3077,10 @@
     "launching": "Launching…",
     "launch": "Brainstorm",
     "noteCreatedIn": "Note created in",
-    "openNotebook": "Open notebook"
+    "openNotebook": "Open notebook",
+    "convertTitle": "Create note from idea",
+    "convertSubtitle": "Choose where to save this note",
+    "ideaLabel": "Idea"
   },
   "byokSettings": {
     "title": "Your API keys (BYOK)",

memento-note/locales/fr.json

@@ -3081,7 +3081,10 @@
     "launching": "Lancement…",
     "launch": "Brainstormer",
     "noteCreatedIn": "Note créée dans",
-    "openNotebook": "Ouvrir le carnet"
+    "openNotebook": "Ouvrir le carnet",
+    "convertTitle": "Créer une note depuis cette idée",
+    "convertSubtitle": "Choisir où sauvegarder cette note",
+    "ideaLabel": "Idée"
   },
   "byokSettings": {
     "title": "Vos clés API (BYOK)",