Teardown astrojs base, use tailwindcss, preact, sitemap

frontend/astro.config.mjs

@@ -1,5 +1,13 @@
 // @ts-check
 import { defineConfig } from 'astro/config';
 
+import tailwind from '@astrojs/tailwind';
+
+import sitemap from '@astrojs/sitemap';
+
+import preact from '@astrojs/preact';
+
 // https://astro.build/config
-export default defineConfig({});
+export default defineConfig({
+  integrations: [tailwind(), sitemap(), preact()]
+});