Update

Server/app/svelte/rollup.config.js

@@ -0,0 +1,97 @@
+import svelte from 'rollup-plugin-svelte';
+import commonjs from '@rollup/plugin-commonjs';
+import resolve from '@rollup/plugin-node-resolve';
+import livereload from 'rollup-plugin-livereload';
+import { terser } from 'rollup-plugin-terser';
+import css from 'rollup-plugin-css-only';
+import cleaner from 'rollup-plugin-cleaner';
+import copy from 'rollup-plugin-copy';
+import watch from "rollup-plugin-watch";
+
+const production = !process.env.ROLLUP_WATCH;
+
+
+function serve() {
+	let server;
+
+	function toExit() {
+		if (server) server.kill(0);
+	}
+
+	return {
+		writeBundle() {
+			if (server) return;
+			server = require('child_process').spawn('npm', ['run', 'start', '--', '--dev'], {
+				stdio: ['ignore', 'inherit', 'inherit'],
+				shell: true
+			});
+
+			process.on('SIGTERM', toExit);
+			process.on('exit', toExit);
+		}
+	};
+}
+    
+const walkSync = require("walk-sync");
+const paths = walkSync("./src", {globs: ["**/*.svelte"]}).map(x => "src/"+x)
+ 
+
+export default {
+	
+	input: paths, 
+	output: { 
+		format: "esm",
+		dir: "../../public/js/components", 
+	},
+	plugins: [
+		svelte({ 
+			compilerOptions: {
+				// enable run-time checks when not in production
+				dev: !production,
+				customElement: true,
+			}
+		}),
+		// we'll extract any component CSS out into
+		// a separate file - better for performance
+		css({ output: 'bundle.css' }),
+
+		// If you have external dependencies installed from
+		// npm, you'll most likely need these plugins. In
+		// some cases you'll need additional configuration -
+		// consult the documentation for details:
+		// https://github.com/rollup/plugins/tree/master/packages/commonjs
+		resolve({
+			browser: true,
+			dedupe: ['svelte']
+		}),
+		commonjs(),
+
+		watch({ dir: 'public' }),
+		cleaner({
+			targets: [
+			  '../../../public/js/components'
+			]
+		}),
+		copy({
+			targets: [
+			  { src: 'public/*', dest: '../../public/' }, 
+			]
+		}),
+
+
+		// In dev mode, call `npm run start` once
+		// the bundle has been generated
+		!production && serve(),
+
+		// Watch the `public` directory and refresh the
+		// browser on changes when not in production
+		!production && livereload('public'),
+
+		// If we're building for production (npm run build
+		// instead of npm run dev), minify
+		production && terser()
+	],
+	watch: {
+		clearScreen: false
+	}
+};