test(ios): cover context erasure and native capability restrictions

Add Apple-platform tests without presenting them as Linux results. Improve native dark-mode contrast and keep the portable policy suite separate from WebKit tests. Swift formatting and syntax checks pass; Xcode execution remains required.

ios/Package.swift

@@ -12,6 +12,7 @@ let package = Package(
                 "AuthenticationView.swift", "BrowserModel.swift", "ContentView.swift",
                 "ServerProbe.swift", "YuvomiApp.swift", "PrivacyInfo.xcprivacy", "Assets.xcassets",
             ], sources: ["ServerAddress.swift", "ServerMetadata.swift"]),
-        .testTarget(name: "YuvomiPolicyTests", dependencies: ["Yuvomi"], path: "Tests"),
+        .testTarget(
+            name: "YuvomiPolicyTests", dependencies: ["Yuvomi"], path: "Tests", exclude: ["BrowserModelTests.swift"]),
     ]
 )