fix(deps): update dependency zod to v4

Author: renovate[bot]

package.json

@@ -62,7 +62,7 @@
     "@modelcontextprotocol/sdk": "^1.17.5",
     "file-type": "^21.0.0",
     "https-proxy-agent": "^7.0.6",
-    "zod": "^3.25.76"
+    "zod": "^4.1.12"
   },
   "devDependencies": {
     "@anthropic-ai/dxt": "^0.2.6",