restore: original UI views from first build, keep fixed models/API

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ios/Platform/Platform/ContentView.swift

@@ -6,10 +6,8 @@ struct ContentView: View {
     var body: some View {
         Group {
             if authManager.isCheckingAuth {
-                ProgressView("Loading...")
-                    .frame(maxWidth: .infinity, maxHeight: .infinity)
-                    .background(Color.canvas)
-            } else if authManager.isLoggedIn {
+                LoadingView(message: "Checking session...")
+            } else if authManager.isAuthenticated {
                 MainTabView()
             } else {
                 LoginView()
@@ -22,22 +20,18 @@ struct ContentView: View {
 }
 
 struct MainTabView: View {
-    @State private var selectedTab = 0
-
     var body: some View {
-        TabView(selection: $selectedTab) {
+        TabView {
             HomeView()
                 .tabItem {
                     Label("Home", systemImage: "house.fill")
                 }
-                .tag(0)
 
             FitnessTabView()
                 .tabItem {
-                    Label("Fitness", systemImage: "figure.run")
+                    Label("Fitness", systemImage: "flame.fill")
                 }
-                .tag(1)
         }
-        .tint(.accentWarm)
+        .tint(Color.accentWarm)
     }
 }