feat(npcs): drop binding; select NPCs on storyline export

Remove storyline/scene NPC binding and export chosen NPCs with relations/groups. Harden export modal so a missing npcs payload no longer blacks out the editor.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/renderer/editor/main.tsx

@@ -2,6 +2,7 @@ import React from 'react';
 import { createRoot } from 'react-dom/client';
 
 import '../shared/ui/globals.css';
+import { WindowErrorBoundary } from '../shared/ui/WindowErrorBoundary';
 import { EditorApp } from './EditorApp';
 import { EditorI18nProvider } from './i18n/EditorI18nContext';
 
@@ -12,8 +13,10 @@ if (!rootEl) {
 
 createRoot(rootEl).render(
   <React.StrictMode>
-    <EditorI18nProvider>
-      <EditorApp />
-    </EditorI18nProvider>
+    <WindowErrorBoundary title="Редактор">
+      <EditorI18nProvider>
+        <EditorApp />
+      </EditorI18nProvider>
+    </WindowErrorBoundary>
   </React.StrictMode>,
 );