Adjust prerender handling for prod build

svelte.config.js

@@ -6,7 +6,18 @@ const config = {
 	// Consult https://svelte.dev/docs/kit/integrations
 	// for more information about preprocessors
 	preprocess: vitePreprocess(),
-  kit: { adapter: adapter() }
+	kit: {
+		adapter: adapter(),
+		prerender: {
+			handleHttpError: ({ status, path }) => {
+				if (status === 404) {
+					console.warn(`Skipping prerender of ${path} (expected 404)`);
+					return;
+				}
+				throw new Error(`${status} ${path}`);
+			}
+		}
+	}
 };
 
 export default config;