Add dynamic ASCII banners and security quotes on startup

[msalihberk]

Description:
To enhance the CLI user experience, the tool should display a stylized ASCII banner and a random educational or cybersecurity-related quote every time the server boots up.

Expected Behavior:
Introduce a dedicated display function that runs immediately when Shadow.py is executed.

Files to look at:

1. mainclass/system.py: Define a function (e.g., show_banner()) that contains an array of security-related quotes and prints a randomized one using colorama for styling.

2. Shadow.py: Call this function at the very beginning of the execution flow.

[kanika021105]

Hi! I'd like to work on this issue .