Project upgraded to Unity 6, including MacOS Silicon Version

2.98.403

• Upgraded project from Unity 2020 to Unity 6.3, mainly to enable MacOS Silicon builds and extend longevity of the project.
• Fixed some UI issues with the print shop's graphic designer controls when on a screen narrower than 16:9 aspect ratio.
• Improved custom t-shirt colors to be closer to what it looks like in the designer preview.