[ImgBot] Optimize images

*Total -- 637.21kb -> 595.56kb (6.54%)

/public/og-image.png -- 298.72kb -> 257.21kb (13.9%)
/public/logos/GitHub.svg -- 3.17kb -> 3.15kb (0.52%)
/public/favicon.svg -- 1.01kb -> 1.01kb (0.29%)
/src/assets/background.svg -- 1.42kb -> 1.42kb (0.07%)
/public/logos/OSUC.svg -- 4.28kb -> 4.28kb (0.07%)
/public/logos/UC.svg -- 325.76kb -> 325.65kb (0.04%)
/src/assets/astro.svg -- 2.85kb -> 2.84kb (0.03%)

Signed-off-by: ImgBotApp <[email protected]>

Author: ImgBotApp