How would you design a strategy to load, monitor, and sandbox third-party scripts (analytics, chat widgets, tag managers) without hurting Core Web Vitals?

Imagine you're building with LEGOs, and your friend wants to add their special blocks to your castle. You need to check if their blocks are safe, put them in a special corner so they don't break your castle, and watch to make sure they don't make your castle slow. That's what we do with third-party scripts on websites.