Socket: ✨ Path to Retrieve Last Message ID

[psychology50]

작업 이유

• Continuing from task Api: ✏️ Append UnreadMessageCount Field in the ChatRoomResponse #190.
• The client will send its last read message ID, which the socket server will retrieve and cache in Redis.

작업 사항

• Added message path: chat.message.{chatRoomId}.read.{lastReadMessageId}

리뷰어가 중점적으로 확인해야 하는 부분

• none

발견한 이슈

• none