Merge pull request #25031 from storybookjs/25029-bug-sveltekit-hot-re…

…load-not-working-after-upgrading-to-storybook-76

SvelteKit: Fix HMR not working
(cherry picked from commit 7ffc515)

code/frameworks/sveltekit/src/plugins/mock-sveltekit-stores.ts

@@ -1,17 +1,15 @@
 import { resolve } from 'node:path';
-import { mergeConfig, type Plugin } from 'vite';
+import type { Plugin } from 'vite';
 
 export function mockSveltekitStores() {
   return {
     name: 'storybook:sveltekit-mock-stores',
-    enforce: 'post',
-    config: (config) =>
-      mergeConfig(config, {
-        resolve: {
-          alias: {
-            $app: resolve(__dirname, '../src/mocks/app/'),
-          },
+    config: () => ({
+      resolve: {
+        alias: {
+          $app: resolve(__dirname, '../src/mocks/app/'),
         },
-      }),
+      },
+    }),
   } satisfies Plugin;
 }