chore: can't find @tailwindcss/node type file (#14475)

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```ts
// error: can't find `@tailwindcss/node` types file
import { compile } from '@tailwindcss/node';
```

packages/@tailwindcss-node/package.json

@@ -23,7 +23,7 @@
   },
   "exports": {
     ".": {
-      "types": "./dist/index.d.mjs",
+      "types": "./dist/index.d.ts",
       "import": "./dist/index.mjs",
       "require": "./dist/index.js"
     },