fix(route): decouple sidebar selection write-back from route publish

The same-value guard only stopped same-value selection re-syncs.
After an external navigation (add menu, rule editor dismissal,
manage-servers/show-runtime actions) the sidebar List still held
its stale cached selection and wrote it back into the custom
selection binding during a view update; the resulting publish
warned and would bounce the navigation back. Route the sidebar
selection through a SwiftUI-managed @State with onChange hops in
both directions (selection -> navigate, route -> backfill), anchor
the seed on WorkspaceRoute.initialDestination, and pin the
alignment with a regression test.

ShadowsocksX-NG2/App/MainWindowView.swift

@@ -44,6 +44,13 @@ struct MainWindowView: View {
   let configurationGroupFileExporter: any ConfigurationGroupFileExporter
 
   @StateObject private var homeServerList = HomeServerListState()
+  /// 侧栏选中项中转：macOS 的 List/NavigationSplitView 会在视图更新期间回写
+  /// selection（选择再同步，且可能携带缓存的旧值），回写必须落在 SwiftUI 自管
+  /// 的 @State 上，再经 onChange 单向驱动 route；直接 publish 到 route 会触发
+  /// view-update 期间发布警告，且缓存的旧值会把外部导航弹回。route 的外部
+  /// 导航（添加菜单、规则编辑器返回等）经 sidebar 上的 onChange 回填选中项。
+  /// 初值须与 WorkspaceRoute 的初始 destination 对齐，否则首帧侧栏无高亮行。
+  @State private var sidebarSelection: WorkspaceDestination? = WorkspaceRoute.initialDestination
   @State private var selection: NodeID?
   @State private var ruleDraft: CustomRuleDraft?
   /// 全局添加菜单打开的表单，以及诊断导出由窗口壳持有。
@@ -271,7 +278,7 @@ extension MainWindowView {
   // MARK: - 侧栏
 
   private var sidebar: some View {
-    List(selection: navigationBinding) {
+    List(selection: $sidebarSelection) {
       Section {
         ForEach(WorkspaceDestination.allCases) { destination in
           sidebarRow(destination)
@@ -280,6 +287,17 @@ extension MainWindowView {
       }
     }
     .listStyle(.sidebar)
+    // 点击行 → @State 选中项 → route；nil 回写无对应 destination，忽略。
+    .onChange(of: sidebarSelection) { _, destination in
+      guard let destination else { return }
+      route.navigate(to: destination)
+    }
+    // route 的外部导航 → 回填选中项；等值不写，避免导航回声。
+    .onChange(of: route.destination) { _, destination in
+      if sidebarSelection != destination {
+        sidebarSelection = destination
+      }
+    }
     .safeAreaInset(edge: .top, spacing: 4) { identityHeader }
     .safeAreaInset(edge: .bottom, spacing: 4) { statusCard }
   }
@@ -319,15 +337,6 @@ extension MainWindowView {
     }
   }
 
-  private var navigationBinding: Binding<WorkspaceDestination?> {
-    Binding(
-      get: { route.destination },
-      set: { destination in
-        guard let destination else { return }
-        route.navigate(to: destination)
-      })
-  }
-
   /// 行尾数量角标：服务器 = 目录树内服务器叶子数；订阅 = 订阅数。
   private func badgeCount(for destination: WorkspaceDestination) -> Int? {
     switch destination {

ShadowsocksX-NG2/App/WorkspaceRoute.swift

@@ -25,12 +25,17 @@ final class WorkspaceRoute: ObservableObject {
   /// scene id 散落（架构测试锚定）。
   static let workspaceSceneID = "workspace"
 
-  @Published private(set) var destination: WorkspaceDestination = .home
+  /// 实例初始 destination。MainWindowView 侧栏 @State 选中项的初值须与此
+  /// 对齐，否则首帧侧栏无高亮行。
+  static let initialDestination: WorkspaceDestination = .home
+
+  @Published private(set) var destination: WorkspaceDestination = initialDestination
 
   /// workspace 内部导航只改变 route destination；开窗不由 route 驱动。
-  /// 同值导航必须是无操作：macOS 的 List/NavigationSplitView 会在视图更新
-  /// 期间回写 selection Binding（选择再同步），此时 publish 会触发
-  /// "Publishing changes from within view updates" 运行时警告。
+  /// 同值导航必须是无操作：外部导航经 onChange 回填侧栏选中项后会再触发
+  /// 一次 selection onChange（导航回声），由同值短路变成无操作；publish
+  /// 一旦发生在视图更新期间（List/NavigationSplitView 的选择再同步回写）
+  /// 会触发 "Publishing changes from within view updates" 运行时警告。
   func navigate(to destination: WorkspaceDestination) {
     guard destination != self.destination else { return }
     self.destination = destination

ShadowsocksX-NG2/Tests/WorkspaceRouteTests.swift

@@ -10,6 +10,12 @@ final class WorkspaceRouteTests: XCTestCase {
     XCTAssertEqual(WorkspaceRoute().destination, .home)
   }
 
+  /// 侧栏 @State 选中项的初值锚定在 initialDestination 上（见 MainWindowView）；
+  /// 两者脱钩会导致首帧侧栏无高亮行。
+  func testInitialDestinationConstantMatchesFreshRoute() {
+    XCTAssertEqual(WorkspaceRoute.initialDestination, WorkspaceRoute().destination)
+  }
+
   /// 侧栏 List/NavigationSplitView 会在视图更新期间回写 selection Binding；
   /// 同值导航不得 publish（否则触发 view-update 期间发布警告）。
   func testNavigateToCurrentDestinationDoesNotPublish() {