Implement an asyncio-based chat server

Async Chat Server (Python asyncio)

Implement a TCP chat server using Python asyncio.

Part 1 — Single global room

Your server listens on a given port and supports multiple concurrent clients.

Protocol (line-based text):

• When a client connects, the server prompts for a username (single line).
• After login, each line a client sends is treated as a chat message.
• The server broadcasts each message to all other connected clients in the format:
  • <username>: <message>

Behavior requirements:

• A client should not receive its own message back.
• Handle client disconnects gracefully (no crashes; cleanup resources).
• The server should continue serving other clients if one client misbehaves (e.g., disconnects mid-line).

Part 2 — Basic chat commands

Extend the protocol to support:

• /join <room> : join (and create if needed) a named room.
  • Each user is in exactly one room at a time .
  • After joining, broadcasts only go to users in the same room .
• /who : return the list of usernames currently in the user’s room.
• /quit : disconnect.

Constraints / assumptions:

• Up to ~1,000 concurrent connections.
• Use only standard library ( asyncio / socket / etc.).
• Favor clear concurrency handling and correctness over advanced features (no persistence required).