fix: correct offset for active toc item (#233)

![2025-01-06_15-12-38](https://github.com/user-attachments/assets/eeda6f2f-216d-42b7-ab5c-e50682bcba4f)

```release-note
修复文章目录激活项偏移错误的问题
```

src/main.ts

@@ -50,6 +50,7 @@ export function generateToc() {
     collapseDepth: 6,
     headingsOffset: 100,
     scrollSmooth: false,
+    tocScrollOffset: 50,
   });
 }