Update dependency tailwindcss to v4

Author: renovate[bot]

package.json

@@ -57,7 +57,7 @@
     "eslint-config-next": "^16.0.7",
     "postcss-preset-env": "^10.4.0",
     "prettier": "^3.7.4",
-    "tailwindcss": "^3.4.18",
+    "tailwindcss": "^4.1.18",
     "typescript": "^5.9.3"
   }
 }