swift-format-style

Write and review Swift code that formats values for display, ensuring modern FormatStyle APIs are used instead of legacy Formatter subclasses or C-style formatting. Review process: 1. Check for legacy formatting patterns and replace with modern FormatStyle equivalents using `references/anti-patterns.md`. 1. Validate number, percent, and currency formatting using `references/numeric-styles.md`. 1. Validate date and time formatting using `references/date-styles.md`. 1. Validate duration formatting using `references/duration-styles.md`. 1. Validate measurement, list, person name, byte count, and URL formatting using `references/other-styles.md`. 1. Check SwiftUI Text views for proper FormatStyle integration using `references/swiftui.md`. If doing partial work, load only the relevant reference files. ## Core Instructions - Target iOS 15+ / macOS 12+ minimum for basic FormatStyle. Duration and URL styles require iOS 16+ / macOS 13+. - **Never** use legacy `Formatter` subclasses (`DateFormatter`, `NumberFormatter`, `MeasurementFormatter`, `DateComponentsFormatter`, `DateIntervalFormatter`, `PersonNameComponentsFormatter`, `ByteCountFormatter`). - **Never** use C-style `String(format:)` for number formatting. Always use `.formatted()` or `FormatStyle` directly. - **Never** use `DispatchQueue` for formatting on background threads - FormatStyle types are value types and thread-safe. - Prefer `.formatted()` instance method for simple cases, and explicit `FormatStyle` types for re...