fix(agent-browser): defer preview origin exposure

electron/agent-browser/module.ts

@@ -1944,14 +1944,15 @@ function previewDataInjectionScript(
   if (!serializedOrigin || !serializedValue) {
     throw new Error('Preview data injection value is not serializable');
   }
-  return `if (globalThis.location?.origin === ${serializedOrigin}) {
+  return `(() => {
+  const expectedOrigin = ${serializedOrigin};
+  const value = ${serializedValue};
   Object.defineProperty(globalThis, "__MAKELORE_DATA__", {
-    value: ${serializedValue},
+    get: () => globalThis.location?.origin === expectedOrigin ? value : undefined,
     enumerable: false,
-    writable: false,
     configurable: false,
   });
-}`;
+})();`;
 }
 
 function crossOriginNavigation(previousUrl: string, nextUrl: string): boolean {