refactor: app 组合根与导航

IosClientKit/Sources/App/AppContainer.swift

@@ -0,0 +1,14 @@
+import CoreDomain
+import CoreRepository
+import FeatureHome
+
+/// 手写组合根 / DI 容器（对应 Android Hilt 的 AppContainer）。
+@MainActor
+public enum AppContainer {
+    /// 装配 FeatureHome 依赖并返回 ViewModel。
+    public static func makeHomeViewModel() -> HomeViewModel {
+        let repository: HomeRepository = FakeHomeRepository()
+        let useCase = HomeUseCase(repository: repository)
+        return HomeViewModel(homeUseCase: useCase)
+    }
+}

IosClientKit/Sources/App/AppRootView.swift

@@ -0,0 +1,36 @@
+import SwiftUI
+import CoreUI
+import FeatureAuth
+import FeatureHome
+
+public struct AppRootView: View {
+    @State private var homeViewModel: HomeViewModel
+
+    public init() {
+        _homeViewModel = State(initialValue: AppContainer.makeHomeViewModel())
+    }
+
+    public var body: some View {
+        TabView {
+            NavigationStack {
+                HomeScreen(viewModel: homeViewModel)
+            }
+            .tabItem { Label("首页", systemImage: "house.fill") }
+
+            NavigationStack {
+                PlaceholderView("计划", systemImage: "calendar")
+            }
+            .tabItem { Label("计划", systemImage: "calendar") }
+
+            NavigationStack {
+                PlaceholderView("打卡", systemImage: "checkmark.seal.fill")
+            }
+            .tabItem { Label("打卡", systemImage: "checkmark.seal.fill") }
+
+            NavigationStack {
+                AuthScreen()
+            }
+            .tabItem { Label("我的", systemImage: "person.crop.circle") }
+        }
+    }
+}