feat(codemode): math parity (#35609)

packages/codemode/src/tool-runtime.ts

@@ -274,6 +274,16 @@ const copyBounded = (
 
   if (Array.isArray(value)) {
     const copied = value.map((item) => copyBounded(item, label, depth + 1, seen, preserveSandboxValues))
+    if (preserveSandboxValues) {
+      // Array metadata is not serialized, but intra-sandbox copies must retain it.
+      for (const [key, item] of Object.entries(value)) {
+        if (Object.hasOwn(copied, key)) continue
+        if (isBlockedMember(key)) {
+          throw new ToolRuntimeError("InvalidDataValue", `${label} contains blocked property '${key}'.`)
+        }
+        Reflect.set(copied, key, copyBounded(item, label, depth + 1, seen, true))
+      }
+    }
     seen.delete(value)
     return copied
   }