Add Clear Screen (0x7) Command Support

[MungaSoftwiz]

Description: This PR introduces support for the Clear Screen (0x7) Command.
closes #6

Key Changes:

• Added the clear_screen function to clear the screen buffer and reset the state.
• Updated the main function to handle 0x7 as a special case (no additional data required).
• Ensures the program displays the cleared screen and provides a success message.

How to Test:

• Run the program and enter 0x7 as the command.
• Verify that the screen is cleared without requiring further input.
• Ensure all other commands continue to function as expected.