Add managed UIKit iOS client

docs/building.md

@@ -31,7 +31,7 @@ and *how to drive the binaries by hand*.
 | Windows client (C# / WinForms) | [§7](#7-windows-client-c--winforms) | `dotnet build clients/windows/VoiceCat.slnx` |
 | Managed macOS client (C# AppKit) | [§8](#8-macos-client-appkit) | `dotnet build clients/apple/dotnet/VoiceCat.Apple.slnx` |
 | Swift macOS migration oracle | [§8](#8-macos-client-appkit) | `scripts/build-macos-client.sh` |
-| iOS client (SwiftUI / simulator) | [§9](#9-ios-client-swiftui) | `scripts/build-ios-client.sh` |
+| Managed iOS client (C# UIKit / simulator) | [§9](#9-ios-client-uikit) | `./dotnet/build-native-ios.sh && dotnet build clients/apple/dotnet/VoiceCat.iOS/VoiceCat.iOS.csproj` |
 | Launch iOS app on simulator | [§9](#9-ios-client-swiftui) | `scripts/run-ios-simulator.sh` |
 | Swift core + tests | [§8](#8-macos-client-appkit) | `cd clients/apple && swift test` |
 
@@ -419,7 +419,21 @@ Or use the per-artifact script which builds and stages to `dist/macos-client/`:
 scripts/build-macos-client.sh
 ```
 
-## 9. iOS client (SwiftUI)
+## 9. iOS client (UIKit)
+
+The replacement iOS client is a native C# UIKit app at
+`clients/apple/dotnet/VoiceCat.iOS`. Build its static media shim and simulator bundle with:
+
+```bash
+./dotnet/build-native-ios.sh
+dotnet restore clients/apple/dotnet/VoiceCat.Apple.slnx
+dotnet build clients/apple/dotnet/VoiceCat.iOS/VoiceCat.iOS.csproj \
+  -c Debug -r iossimulator-arm64 --no-restore
+```
+
+The build invokes Xcode for the retained Swift ReplayKit extension and embeds the resulting
+appex. The older SwiftUI application below remains the migration oracle during parity and
+physical-device accessibility testing.
 
 The iOS client is an Xcode project (`clients/apple/iOS/VoiceCatiOS.xcodeproj`) that
 links `libvoicecat` via the same `VoiceCatCore` Swift Package as the macOS client.