fix: change process.exit to the closeBundle hook

buildEnd happens before all output files are written causing issues with not including things like storybook's iframe.html

Author: davidpett

src/index.ts

@@ -68,8 +68,9 @@ export const unpluginFactory: UnpluginFactory<Options | undefined> = (options =
       compiler = await createCompiler(validated.config)
       buildQueue = new BuildQueue(compiler)
     },
-    async buildEnd() {
-      // ensure the process exits when the build is finished
+    async closeBundle() {
+      // Use closeBundle instead of buildEnd to ensure all output files
+      // (including iframe.html in Storybook builds) are written before exiting
       process.exit(0)
     },
     /**