fix: add empty transform to vite scan plugin for Vite 7.0+ compatibility

Fixes #19376 - Cannot read properties of undefined (reading 'call')

- Added empty transform() function to @tailwindcss/vite:scan plugin
- Returns null to tell Vite to skip transformation for this plugin
- Prevents undefined error when Vite 7.0+ tries to call plugin.transform.call()
- Maintains backward compatibility with older Vite versions

Author: ath1614

packages/@tailwindcss-vite/src/index.ts

@@ -114,6 +114,11 @@ export default function tailwindcss(opts: PluginOptions = {}): Plugin[] {
           minify = opts.optimize.minify !== false
         }
       },
+
+      // Add empty transform to prevent Vite 7.0+ from trying to call undefined transform
+      transform() {
+        return null
+      },
     },
 
     {