Issue#6: Implement visually stunning ASCII Art Intro Screen

[AyeongKwon]

🚀 Overview

This PR addresses issue #6 by implementing the core User Interface for the application's entry point, the Intro Screen.

The primary goal of this change is to provide a visually striking and aesthetically pleasing terminal interface upon program startup, guiding the user to the next step (data input).

✨ Key Changes

• New File Added: Implemented IntroScreen.java containing all the UI logic.
• Aesthetic Design: Utilizes ANSI Escape Codes to achieve a colorful and styled presentation (using Cyan, Green, Yellow, and a Rainbow gradient for the logo).
• Project Branding: Implemented the UniTime-Solver logo as multi-colored ASCII Art, centered within the display.
• Structure: The entire UI is enclosed within a clear Bordered Box (Terminal UI Box) for a professional look.
• User Prompt: Added a clear prompt to instruct users to press [ENTER] to begin data input.

Check:
* Confirm the overall screen (borders, text) is correctly centered according to the defined terminal width (80 characters).
* Verify that the ANSI colors and bold formatting are displayed correctly in your terminal environment.
* Ensure the ASCII Art logo displays the intended multi-color effect.

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The image below shows the result of executing the IntroScreen.java.

[ljseop1030]

I can see you effort in the logo. 👍
What is the meaning of Done in the execution screen?
Does the "[Enter] to start UniTime_Solver" actually work in this code? Or do we have to add it afterwards?

[AyeongKwon]

Hello, thank you for the review and the detailed feedback.😊

1. Done
   Done means the program is successfully opened and the introscreen finished loading.
   I think this phrase is a little ambiguous, so I fixed it!

2. [Enter] to start UniTime_Solver
   For now, the prompt is only visual. We have to add "[Enter] to start UniTime_Solver" function afterward.

I've noted these points for future improvement! Thanks!

[mingyeonggg]

Wow the logo looks amazing!! I really love how fancy and vibrant it is. It must have been a lot of work to create this. Great job! 💯 💯 💯

[Kimhyewon0621]

Excellent work on Intro Screen 🎨

The Intro Screen Looks Good To Me. The use of Rainbow makes our program more brighltly.

Also the instruction to press [ENTER] is clear and user-friendly.

Approved! LGTM 🚀