uikit-expertlisted

# UIKit Expert Skill ## Overview Use this skill to build, review, or improve UIKit features with correct lifecycle management, performant Auto Layout, modern collection view APIs, and safe navigation patterns. Prioritize native APIs, Apple's documented best practices, and performance-conscious patterns. This skill focuses on facts and best practices without enforcing specific architectural patterns (no MVVM/VIPER/Coordinator mandates). ## Workflow Decision Tree ### 1) Review existing UIKit code - Check view controller lifecycle usage — `viewIsAppearing` for geometry, `viewDidLoad` for setup only (see `references/view-controller-lifecycle.md`) - Verify Auto Layout correctness — batch activation, no constraint churn, `translatesAutoresizingMaskIntoConstraints` (see `references/auto-layout.md`) - Check collection/table view APIs — diffable data sources, stable identity, CellRegistration (see `references/modern-collection-views.md`) - Verify cell configuration uses `UIContentConfiguration`, not deprecated `textLabel` (see `references/cell-configuration.md`) - Check list scroll performance — prefetching, cell reuse cleanup, reconfigureItems (see `references/list-performance.md`) - Verify navigation patterns — bar appearance all 4 slots, no concurrent transition crashes (see `references/navigation-patterns.md`) - Check animation correctness — API selection, PropertyAnimator state machine, constraint animation (see `references/animation-patterns.md`) - Audit memory management — `