fix: apply filter for css-post plugin and json plugin

this was not working because of vitejs#19586 (comment) and vitejs#19878

Author: sapphi-red

packages/vite/src/node/plugins/css.ts

@@ -1095,8 +1095,10 @@ export function cssPostPlugin(config: ResolvedConfig): Plugin {
 
   // backward compat
   const handler = plugin.transform.handler
+  const filter = plugin.transform.filter
   ;(plugin as any).transform = handler
   ;(plugin as any).transform.handler = handler
+  ;(plugin as any).transform.filter = filter
 
   return plugin
 }

packages/vite/src/node/plugins/json.ts

@@ -129,8 +129,10 @@ export function jsonPlugin(
 
   // backward compat
   const handler = plugin.transform.handler
+  const filter = plugin.transform.filter
   ;(plugin as any).transform = handler
   ;(plugin as any).transform.handler = handler
+  ;(plugin as any).transform.filter = filter
 
   return plugin
 }