ios: show provider/model in subtitle

ios/Packages/Sybil/Sources/Sybil/SybilWorkspaceView.swift

@@ -232,13 +232,7 @@ struct SybilWorkspaceView: View {
         HStack(spacing: 14) {
             workspaceNavigationLeadingControl
 
-            Text(viewModel.selectedTitle)
-                .font(.sybil(size: 16, weight: .semibold))
-                .foregroundStyle(SybilTheme.text)
-                .lineLimit(1)
-                .minimumScaleFactor(0.78)
-                .frame(maxWidth: .infinity, alignment: .leading)
-                .multilineTextAlignment(.leading)
+            customWorkspaceNavigationTitle
 
             workspaceNavigationTrailingControl
         }
@@ -251,6 +245,32 @@ struct SybilWorkspaceView: View {
         }
     }
 
+    private var selectedProviderModelSubtitle: String {
+        let selectedModel = viewModel.model.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !selectedModel.isEmpty else {
+            return viewModel.provider.displayName
+        }
+        return "\(viewModel.provider.displayName) • \(selectedModel)"
+    }
+
+    private var customWorkspaceNavigationTitle: some View {
+        VStack(alignment: .leading, spacing: 2) {
+            Text(viewModel.selectedTitle)
+                .font(.sybil(size: 16, weight: .semibold))
+                .foregroundStyle(SybilTheme.text)
+                .lineLimit(1)
+                .minimumScaleFactor(0.78)
+
+            Text(selectedProviderModelSubtitle)
+                .font(.sybil(size: 10, weight: .medium))
+                .foregroundStyle(SybilTheme.textMuted)
+                .lineLimit(1)
+                .minimumScaleFactor(0.82)
+        }
+        .frame(maxWidth: .infinity, alignment: .leading)
+        .multilineTextAlignment(.leading)
+    }
+
     @ViewBuilder
     private var workspaceNavigationLeadingControl: some View {
         switch navigationLeadingControl {