Add native iOS automation validation foundation

[JaysonAlbert]

Summary

• add Phase 9 documentation for native iOS automation validation and Maestro flows
• add deterministic iOS automation launch scenarios and stable accessibility identifiers
• add a repository-owned Maestro workspace plus a simulator install helper script

Validation

• swift test (apps/ios-native/PicsewApp)
• npm run typecheck
• npm run lint (warnings only in existing Playwright tests; no errors)
• xcodebuild -project apps/ios-native/HostApp/PicsewNativeApp.xcodeproj -scheme PicsewNativeApp -destination 'generic/platform=iOS Simulator' CODE_SIGNING_ALLOWED=NO build

Notes

• Maestro smoke flows are included in the repo, but this environment currently has the Maestro desktop app cask rather than the Maestro CLI binary in PATH.