move frontend to a cmd too for consistency

cmd/frontend/svelte.config.js

@@ -0,0 +1,18 @@
+import adapter from '@sveltejs/adapter-static';
+import { vitePreprocess } from '@sveltejs/vite-plugin-svelte';
+
+/** @type {import('@sveltejs/kit').Config} */
+const config = {
+	preprocess: vitePreprocess(),
+	kit: {
+		adapter: adapter({
+			pages: 'build',
+			assets: 'build',
+			fallback: undefined,
+			precompress: false,
+			strict: true
+		})
+	}
+};
+
+export default config;