fix: use vercel image provider for production deployment

[Joehoel]

Problem

Images are not loading on the production site at joelkuijper.me.

Root Cause

The site uses @nuxt/image with the ipx provider, but it's deployed on Vercel with prerendering enabled (routeRules: '/**': { prerender: true }).

The IPX provider doesn't work correctly with this setup because:

• IPX requires server-side processing to handle /_ipx/ image transformation routes
• With prerendering, pages are statically generated at build time
• The prerendered pages reference /_ipx/ URLs that don't exist in the static output

Solution

Switch to Vercel's native image provider (provider: 'vercel') which:

• Uses Vercel's CDN for on-demand image optimization
• Works correctly with prerendered/static pages
• Is automatically detected on Vercel deployments (when not overridden by an explicit provider setting)

Changes

• nuxt.config.ts: Changed image.provider from 'ipx' to 'vercel'

Testing

After merging, deploy to Vercel and verify images load correctly on:

• Blog post cover images (e.g., posts with coverImage set)