Fix Vercel SPA routing with rewrite config

[MelonChicken]

Summary

• Added vercel.json to support client-side routing on Vercel.
• Redirects all routes to index.html so React Router can handle page navigation.

Why

When users directly access or refresh routes like /shop, /login, or /archive, Vercel tries to find those paths as real server files and returns 404 NOT_FOUND.

This rewrite ensures that Vercel serves the frontend app first, and then React Router handles the route internally.

Changes

• Added vercel.json
• Configured rewrite rule:

{
  "rewrites": [
    {
      "source": "/(.*)",
      "destination": "/index.html"
    }
  ]
}

How to Test

1. Open the deployed site. (https://memory-egg-front.vercel.app/)
2. Navigate to pages such as /shop, /login, or /archive.
3. Refresh the page directly on those routes.
4. Confirm that the page loads without 404 NOT_FOUND.