fix(phase2): restore agent streams and persist extension installations

frontend/src/features/editor/EditorPane.spec.ts

@@ -52,7 +52,7 @@ describe('EditorPane file switching', () => {
 
     expect(store.currentFilePath).toBe('/数据结构/红黑树.md')
     expect(wrapper.text()).not.toContain('祝你写作愉快')
-  })
+  }, 15000) // Real Milkdown is now imported lazily; cold module transforms count toward this integration test.
 
   it('applies the saved spell-check and language settings to source mode', async () => {
     const editor = useEditorStore()

frontend/src/features/editor/EditorPane.vue

@@ -1,9 +1,9 @@
 <script setup lang="ts">
-import { ref, watch } from 'vue'
+import { defineAsyncComponent, ref, watch } from 'vue'
 import { useEditorStore } from '@/stores/editor'
 import { useSettingsStore } from '@/stores/settings'
 import { useThemeStore } from '@/stores/theme'
-import VisualMarkdownEditor from './VisualMarkdownEditor.vue'
+const VisualMarkdownEditor = defineAsyncComponent(() => import('./VisualMarkdownEditor.vue'))
 
 const editorStore = useEditorStore()
 const settingsStore = useSettingsStore()