fix: support node 22 (#142)

Author: joshsny

package.json

@@ -85,7 +85,7 @@
     "typescript": "^5.0.4"
   },
   "engines": {
-    "node": "18.x || 20.x",
+    "node": ">=18",
     "npm": ">=3.10.7"
   },
   "packageManager": "pnpm@9.15.5+sha256.8472168c3e1fd0bff287e694b053fccbbf20579a3ff9526b6333beab8df65a8d",
@@ -142,7 +142,7 @@
   "author": "PostHog",
   "license": "MIT",
   "volta": {
-    "node": "18.20.8",
+    "node": "20.18.2",
     "pnpm": "9.15.5"
   }
 }