fix: ensure svelte modules correctly run in DEV mode (#906)

* fix: ensure svelte modules correctly run in DEV mode

* lint

* change to patch

Author: trueadm

.changeset/long-suns-happen.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/vite-plugin-svelte': patch
+---
+
+fix: ensure svelte modules correctly run in DEV mode

packages/vite-plugin-svelte/src/index.js

@@ -200,6 +200,7 @@ export function svelte(inlineOptions) {
 				}
 				try {
 					const compileResult = svelteCompiler.compileModule(code, {
+						dev: !viteConfig.isProduction,
 						generate: ssr ? 'server' : 'client',
 						filename: moduleRequest.filename
 					});