Updated SKILL.md to reference project concurrency settings and added a new reference guide for Swift 6.2 approachable concurrency mode. The new guide covers detection, expected behavior changes, recommended fixes, and common pitfalls for projects using main-actor-by-default and default actor isolation.
Added a new reference file summarizing SwiftUI-specific concurrency guidance from WWDC, covering actor isolation, Sendable closures, and async work structuring. Updated SKILL.md to include a link to this new reference for easier access to SwiftUI concurrency best practices.
