fix(vite-plugin-nitro): use proxy for API requests instead of custom middleware

[brandonroberts]

PR Checklist

Closes #

What is the new behavior?

Introduces the useAPIMiddleware flag for the platform package.

import { defineConfig } from 'vite';
import analog from '@analogjs/platform';

// https://vitejs.dev/config/
export default defineConfig(({ mode }) => ({
  plugins: [analog({
    useAPIMiddleware: false,
  })],

}));

API routes are built under /api during development, and / in the production build, and requests made to /api routes are configured using custom internal middleware. This flag disables the custom internal middleware and uses routeRules to proxy the request instead, which allows the API routes to properly preserve cookies and headers with direct requests and redirects.

• Existing routeRules configuration is merged with the internal configuration if provided.
• The prevents a breaking change when used with Cloudflare

Does this PR introduce a breaking change?

• Yes
• No

Other information

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[andreascorti]

Thanks a lot @brandonroberts for this fix! Really appreciated!

[osnoser1]

I was checking what was happening with the headers that weren't being set in prod using Vercel for a couple of days. Initially I thought it was a problem with h3 in Vercel, but in the end, I figured out the problem could be in the nitro vite plugin but I hadn't a chance to keep digging.

I really appreciate this fix @brandonroberts, thanks 😄