fix(deps): update dependency zod to v4

Author: renovate[bot]

package.json

@@ -104,7 +104,7 @@
     "vega": "5.33.0",
     "vega-lite": "5.11.0",
     "yup": "1.7.1",
-    "zod": "3.25.76",
+    "zod": "4.2.1",
     "zod4": "npm:zod@next"
   },
   "devDependencies": {