Add inspected agent viewport export with policy-bound final release

apps/browser/page-clipboard-guard.cjs

@@ -52,4 +52,23 @@ function disposePageClipboardGuard(contents){
   owners.delete(contents);owner.healthy=false;owner.api.removeListener('detach',owner.detached);
   if(owner.api.isAttached())owner.api.detach();
 }
-module.exports={attachPageClipboardGuard,guardedScreenshot,disposePageClipboardGuard};
+async function guardedVisualStructure(contents){
+  const owner=owners.get(contents);
+  if(!owner?.healthy||!owner.api.isAttached()||contents.isDestroyed())throw Error('Managed visual export refused');
+  // Native DOM data detects closed/declarative roots that isolated DOM queries
+  // cannot see. It is consumed privately and never logged or returned to agents.
+  const result=await deadline(owner.api.sendCommand('DOM.getDocument',{depth:-1,pierce:true}));
+  if(owners.get(contents)!==owner||!owner.healthy||!owner.api.isAttached())throw Error('Managed visual export refused');
+  const queue=[result?.root];let nodes=0,characters=0;
+  while(queue.length){
+    const node=queue.pop();if(!node||++nodes>20000)throw Error('Managed visual export refused');
+    for(const text of [node.nodeName,node.nodeValue,...(node.attributes||[])]){if(typeof text!=='string'||(characters+=text.length)>1024*1024)throw Error('Managed visual export refused');}
+    const shadows=node.shadowRoots||[],children=node.children||[];
+    if(!Array.isArray(shadows)||!Array.isArray(children)||nodes+queue.length+shadows.length+children.length>20000)throw Error('Managed visual export refused');
+    for(const root of shadows){if(root.shadowRootType==='closed')throw Error('Managed visual export refused');queue.push(root);}
+    if(node.contentDocument)throw Error('Managed visual export refused');
+    queue.push(...children);
+  }
+  return {safe:true,nodes};
+}
+module.exports={attachPageClipboardGuard,guardedScreenshot,guardedVisualStructure,disposePageClipboardGuard};