feat: add popover introduction info for models

[JiaxinD]

New feature: added a popover introduction for home screen's model selector, include info for each model's size, author, quantization, Vram required and more.

Desktop.2024.09.09.-.01.11.28.02.mp4

[Neet-Nestor]

Thanks for the contribution! It looks fine on my end, but for style consistency and package size we tend to not introduce additional packages, especially large ones like material UI unless absolute necessary.

For the popover you used, we have a native Popover implementation at ui-lib.js already. Could you try adopting it to see whether it is working? If so we can avoid introducing both emotion and material UI here.