Async/Await

Summary

Syntactic sugar over Promises that lets asynchronous backend code read top-to-bottom like synchronous code, using `try`/`catch` for error handling.

• 1Rewrite a `.then()` chain (e.g. a DB query then a response) using async/await.
• 2Practice wrapping async route handlers in try/catch to avoid unhandled rejections.
• 3Learn how to run independent async calls in parallel with `Promise.all` instead of sequential awaits.