Here are the classes, structs, unions and interfaces with brief descriptions:
| CChat | A class to handle Chat_test functionalities including sending and retrieving messages |
| CClient | A class to manage the API gateway operations |
| CDialog | Represents a dialog between two users |
| CMessage | Represents a message exchanged between two users |
| CMessage_store | |
| CNetworkMessage | Class representing a message with a type and content |
| CPair | A class to manage user pairs and their similarities |
| CServer | Represents a server that can be started, stopped, and restarted |
| CStorage | A class to manage user data |