Make documentation more clear about vite.config.ts server preset

[JohnCido]

This page seems to be using some old content from 0.3.x era I guess? I set the preset to node since this filed was already set when I'm using 0.3.x version, and the page still says the default preset is node.

But this causes my server to shutdown shortly after start. After checking the Nitro doc, I finally realized the default preset is node-server not node. And after I remove the preset field, my server is finally running.

I understand this might not be a problem for people using create-solid. But when migrating from older versions, this might cause confusion.