chore: update docs

Author: hunghg255

docs/.vitepress/locale.ts

@@ -82,6 +82,10 @@ export function getLocaleConfig(lang: string) {
           text: t('Custom Theme'),
           link: `${urlPrefix}/guide/custom-theme`,
         },
+        {
+          text: t('How to Migrate'),
+          link: `${urlPrefix}/guide/how-to-migrate`,
+        },
       ],
     },
     {

docs/guide/custom-theme.md

@@ -2,8 +2,8 @@
 description: Custom Theme
 
 next:
-  text: Attachment
-  link: /extensions/Attachment.md
+  text: How to Migrate
+  link: /guide/how-to-migrate.md
 ---
 
 # Custom Theme