chore(frontend): pin zod to ^4.3.6 [UX-1332]

Co-Authored-By: Claude <noreply@anthropic.com>

Author: c-julin

frontend/bun.lock

@@ -142,7 +142,7 @@
     "use-stick-to-bottom": "^1.1.1",
     "vaul": "^1.1.2",
     "yaml": "^2.8.3",
-    "zod": "^4.4.3",
+    "zod": "^4.3.6",
     "zustand": "^5.0.8"
   },
   "devDependencies": {