Only output single file on build

vite.config.js

@@ -3,14 +3,16 @@ import { svelte } from '@sveltejs/vite-plugin-svelte'
 import { viteSingleFile } from 'vite-plugin-singlefile'
 
 // https://vite.dev/config/
-export default defineConfig({
+export default defineConfig(({ command }) => ({
   plugins: [
     svelte(),
-    viteSingleFile({
+    ...(command === 'build'
+      ? [viteSingleFile({
           inlineStyles: true,
           inlineScripts: true,
           removeUnusedCss: true,
-    }),
+        })]
+      : []),
   ],
   build: {
     target: 'esnext',
@@ -24,4 +26,4 @@ export default defineConfig({
     setupFiles: ['./tests/setup.js'],
     include: ['src/**/*.test.js', 'tests/**/*.test.js'],
   },
-})
+}))