QA: Headless Chat (Simple) — AG2

• Navigate to /demos/headless-simple
• Verify "Headless Chat (Simple)" heading
• Type "show a card about cats"
• Click Send
• Verify user bubble appears
• Verify assistant replies, ShowCard renders (title + body)

Expected Results

• Custom chat UI works (not pre-built CopilotChat)
• useComponent registration wired via copilotkit.runAgent