Styled Chat Container - Copy this React, Mui Component to your project

Create a Chat UI component with a sidebar that lists contacts, displaying each person's avatar, name, and a snippet of the most recent message. The main section should feature a header with the current chat partner's avatar, name, and online status. Below the header, include a scrollable conversation history with time stamped messages, clearly differentiating between sent and received messages. At the bottom, provide an expandable input field for typing messages, along with a send button. Ensure the design is fully responsive for all devices and includes accessibility features such as keyboard navigation and screen reader support for an inclusive user experience.