chore: update Node.js engine requirement to >=20 (#167) (#168)

Co-authored-by: Furkan Çetinkaya <furkancetinkaya0746@gmail.com>

Author: cortinico

template/package.json

@@ -36,6 +36,6 @@
     "typescript": "^5.8.3"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   }
 }