feat(frontend): 接通完整页面路由与桌面壳层

frontend/src/features/editor/EditorPane.vue

@@ -5,10 +5,12 @@ const editorStore = useEditorStore()
 </script>
 
 <template>
-  <textarea
+<textarea
     class="editor-pane"
+    :class="editorStore.mode"
     :value="editorStore.content"
-    spellcheck="false"
+    :spellcheck="editorStore.mode === 'wysiwyg'"
+    :aria-label="editorStore.mode === 'source' ? 'Markdown 源码编辑器' : 'Markdown 写作编辑器'"
     @input="editorStore.updateContent(($event.target as HTMLTextAreaElement).value); editorStore.scheduleAutoSave()"
   />
 </template>
@@ -26,5 +28,8 @@ const editorStore = useEditorStore()
   color: var(--color-text-primary);
   font: inherit;
   line-height: 1.7;
+  user-select: text;
 }
+.editor-pane.wysiwyg { max-width: 920px; margin: 0 auto; padding: var(--space-3xl) clamp(var(--space-xl), 8vw, 80px); font-family: var(--font-editor-sans); font-size: var(--font-editor-size); line-height: var(--font-editor-line-height); }
+.editor-pane.source { font-family: var(--font-editor-mono); font-size: var(--font-editor-size); line-height: var(--font-editor-line-height); }
 </style>