Caching, Skeleton Loading, and Happy Mac

Caching Implemented comprehensive caching across all AT Protocol data fetches to prevent 504 timeouts on Vercel serverless functions. Data is cached with appropriate TTLs and revalidated in the background. Skeleton loading Added skeleton loaders for all card components matching the shape and size of their real counterparts. Happy Mac Added a Happy Mac easter egg animation triggered by clicking the profile picture multiple times. Includes an ADSR envelope beep sound.