fix(deps): update dependency zod to v4

Author: renovate[bot]

package-lock.json

@@ -20,7 +20,7 @@
     "express": "^5.0.0",
     "js-yaml": "^4.1.1",
     "jsonwebtoken": "^9.0.2",
-    "zod": "^3.22.4"
+    "zod": "^4.0.0"
   },
   "devDependencies": {
     "@types/express": "^5.0.0",