[TASK] Chat Window (Agent Interface)

[PEXEL2002]

Task description and detailed requirements:
Develop the main interaction component for the AI Travel Assistant.

• Create a chat-like UI component (message bubbles).
• Distinguish between "User" messages and "Assistant" responses.
• Implement an input field with a "Send" button.

Definition of task completion:
The UI renders a list of messages, and the input field sends data to a placeholder backend endpoint, displaying a "waiting" state while processing.