feat: native app design review mode

[nutt-adam]

Summary

• /design-review now auto-detects native app projects (Xcode/SwiftUI, Gradle/Android, Flutter, React Native) and enters Native App Mode
• Uses screencapture (macOS) or user-provided screenshots instead of browser automation
• Extracts design tokens from source code (SwiftUI modifiers, Android XML, Flutter themes) instead of JS/CSS evaluation
• Skips web-only phases (responsive, DOM inspection, performance metrics) while keeping all visual audit checklist items that work from screenshots
• Fix loop supports rebuild-relaunch-recapture cycle for native apps

Motivation

We were building a native macOS music player (SwiftUI + MusicKit) and wanted to run /design-review on it. The skill was hardwired to web apps via Playwright. This adds a skill-level native app mode that requires zero changes to the browse binary — it uses OS-level screenshot tools and source code inspection instead.

Files changed

• design-review/SKILL.md.tmpl — native app detection in Setup, native app re-test in fix loop, token-first rule
• scripts/resolvers/design.ts — Native App Mode, source-code design system extraction, native app alternatives for all 10 checklist categories, native interaction flow review
• design-review/SKILL.md — regenerated

Test plan

• Run /design-review on a web project — verify no regression (all existing paths unchanged)
• Run /design-review --native on a SwiftUI project — verify native detection and screenshot fallback
• Run /design-review on an Xcode project directory — verify auto-detection kicks in
• Verify bun run gen:skill-docs succeeds with no errors

🤖 Generated with Claude Code