chore: rollup-plugin-visualizer (#6072)

## Summary

Using this tool, will generates dist/stats.html after build, we can see
the parts that are excessively large when packaged.

```bash
pnpm run build:analyze
```

<img width="2486" height="1780" alt="CleanShot 2025-10-15 at 17 25
17@2x"
src="https://github.com/user-attachments/assets/fd3ff5c9-2e7a-44a0-8b9f-4d87664c848c"
/>


┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6072-chore-rollup-plugin-visualizer-28d6d73d36508184800cf7a67141b782)
by [Unito](https://www.unito.io)

vite.config.mts

@@ -1,6 +1,7 @@
 import tailwindcss from '@tailwindcss/vite'
 import vue from '@vitejs/plugin-vue'
 import dotenv from 'dotenv'
+import { visualizer } from 'rollup-plugin-visualizer'
 import { FileSystemIconLoader } from 'unplugin-icons/loaders'
 import IconsResolver from 'unplugin-icons/resolver'
 import Icons from 'unplugin-icons/vite'
@@ -16,6 +17,7 @@ dotenv.config()
 
 const IS_DEV = process.env.NODE_ENV === 'development'
 const SHOULD_MINIFY = process.env.ENABLE_MINIFY === 'true'
+const ANALYZE_BUNDLE = process.env.ANALYZE_BUNDLE === 'true'
 // vite dev server will listen on all addresses, including LAN and public addresses
 const VITE_REMOTE_DEV = process.env.VITE_REMOTE_DEV === 'true'
 const DISABLE_TEMPLATES_PROXY = process.env.DISABLE_TEMPLATES_PROXY === 'true'
@@ -163,7 +165,21 @@ export default defineConfig({
       deep: true,
       extensions: ['vue'],
       directoryAsNamespace: true
-    })
+    }),
+
+    // Bundle analyzer - generates dist/stats.html after build
+    // Only enabled when ANALYZE_BUNDLE=true
+    ...(ANALYZE_BUNDLE
+      ? [
+          visualizer({
+            filename: 'dist/stats.html',
+            open: false,
+            gzipSize: true,
+            brotliSize: true,
+            template: 'treemap' // or 'sunburst', 'network'
+          })
+        ]
+      : [])
   ],
 
   build: {