Refactor chat room implementation

- Renamed Room class to ChatRoom and updated all references accordingly.
- Removed the old room.cpp and room.h files.
- Updated CMakeLists.txt to include chat_room.cpp instead of room.cpp.
- Modified ChatUser class to use shared_ptr<ChatRoom> instead of shared_ptr<Room>.
- Updated Server class to create instances of ChatRoom instead of Room.
- Removed User class and its associated files, integrating its functionality into ChatUser.
- Ensured all relevant includes and dependencies are updated to reflect the new class structure.

server.cpp

@@ -116,7 +116,7 @@ namespace Yc {
         void Server::createRooms(Json::Value roomList) {
             auto self = shared_from_this();
             for (auto &room: roomList)  {
-                auto newRoom = std::make_shared<Room>(self, room);
+                auto newRoom = std::make_shared<ChatRoom>(self, room);
                 _rooms.push_back(newRoom);
             }
         }