Broaden real repo smoke coverage

[Zach677]

Context

Modern.UIKit is Agent-first. Existing-repo adoption should be proven against real repository shapes before any stronger migration claims.

Current smoke references include SubPanda and selected Dimillian repos. Keep this read-only unless a separate task explicitly asks for code changes in a fixture clone.

Scope

• Add a small, representative smoke matrix for open source Apple repos.
• Cover at least these shapes:
  • SwiftUI + Xcode project
  • Tuist + SwiftUI
  • CocoaPods workspace
  • SwiftPM package-first with nested app project
  • SwiftPM package-only macOS app/tool
  • UIKit/Xcode baseline app when available
• Record scenario, status, goal_supported_level, can_apply, and source_of_truth for each repo.

Acceptance

• Smoke runs are read-only and reproducible.
• Results inform analyzer tests or docs only when they reveal a real gap.
• README stays concise; detailed findings live in issues or test fixtures.

[linear-code]

SPA-55