Allow isr/prerender on Vercel

[jpmaga]

This allows us to use vercel's ISR and prerender functions.

To enable ISR/Prerender, pass in the prerender function.

import { defineConfig } from "vite"
import solid from "solid-start/vite"
import vercel from "solid-start-vercel"

export default defineConfig({
  plugins: [
    solid({
      ssr: true,
      adapter: vercel({
        prerender: true,
      }),
    }),
  ],
})

You can also set the expiration time and/or the bypassToken. (expiration defaults to false, meaning it won't expire)

import { defineConfig } from "vite"
import solid from "solid-start/vite"
import vercel from "solid-start-vercel"

export default defineConfig({
  plugins: [
    solid({
      ssr: true,
      adapter: vercel({
        prerender: {
          expiration: 60,
          bypassToken: "87734ad8259d67c3c11747d3e4e112d0",
        },
      }),
    }),
  ],
})

This code is basically a POC, some things could probably be improved.