chore: add vercel adapter and auth dependencies

apps/blog/astro.config.mjs

@@ -1,4 +1,5 @@
 import { defineConfig } from 'astro/config';
+import vercel from '@astrojs/vercel';
 import remarkDirective from 'remark-directive';
 import remarkGfm from 'remark-gfm';
 import remarkSlug from 'remark-slug';
@@ -7,6 +8,7 @@ import remarkAside from './src/plugins/remark-aside.ts';
 
 export default defineConfig({
   output: 'static',
+  adapter: vercel(),
   markdown: {
     remarkPlugins: [
       remarkGfm,