fix: engine field

mimic `nextjs-openai`

fixes #17

Author: ctjlewis

package.json

@@ -54,7 +54,7 @@
     "yield-stream": "^3.0.0"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=14"
   },
   "keywords": [
     "nextjs",
@@ -76,4 +76,4 @@
       "releaseName": "v${version}"
     }
   }
-}
+}