Explain iOS ARC and avoid retain cycles

## iOS Memory Management (ARC) You have 10 minutes to explain iOS memory management under ARC. Cover the following: 1. **How ARC manages object lifetime** (what it does at compile time, when deallocation happens). 2. The meaning and typical use cases of **strong / weak / unowned** references. 3. **Retain cycles**: - Common places they occur (e.g., closures/blocks, delegate patterns, timers, notification observers). - How to prevent and break cycles. 4. What an **autorelease pool** is and when you might need `@autoreleasepool { ... }`. 5. How you would **debug memory issues** (leaks, unexpectedly retained objects) using Xcode tools. Assume Swift + UIKit/SwiftUI context unless you state otherwise.