feat: add vercel routes config generator

This is so we do not need to force trailing slashes.

svelte.config.js

@@ -1,6 +1,8 @@
 import adapter from '@sveltejs/adapter-static';
 import preprocess from 'svelte-preprocess';
 
+import { wrap } from './src/_vercel-moment.js';
+
 /** @type {import('@sveltejs/kit').Config} */
 const config = {
 	// Consult https://github.com/sveltejs/svelte-preprocess
@@ -9,13 +11,11 @@ const config = {
 
 	kit: {
 		// adapter-static has vercel detection, but that does not let you set a custom 404 page easily.
-		// Instead, we have to disable it and set trailing slash to always.
-		adapter: adapter({
+		// Instead, we have to use a wrapper that generates a vercel config if on vercel...
+		adapter: wrap(adapter, {
 			pages: "public",
 			fallback: "404.html"
 		}),
-
-		trailingSlash: 'always'
 	}
 };