adds quick question UI for mac catalyst target

ios/Packages/Sybil/Sources/Sybil/SplitView.swift

@@ -78,6 +78,7 @@ public struct SplitView: View {
         .font(.sybil(.body))
         .preferredColorScheme(.dark)
         .focusedSceneValue(\.sybilKeyboardActions, keyboardActions)
+        #if !targetEnvironment(macCatalyst)
         .sheet(isPresented: $isQuickQuestionPresented, onDismiss: handleQuickQuestionDismissed) {
             SybilQuickQuestionView(
                 viewModel: viewModel,
@@ -85,7 +86,11 @@ public struct SplitView: View {
             )
             .presentationDragIndicator(.visible)
         }
+        #endif
         .task {
+            #if targetEnvironment(macCatalyst)
+            SybilMacQuickQuestionController.shared.attach(viewModel)
+            #endif
             await viewModel.bootstrap()
             presentPendingQuickQuestionIfPossible()
         }
@@ -107,6 +112,9 @@ public struct SplitView: View {
                 shouldRefreshOnForeground = true
                 viewModel.markAppInactiveForNetwork()
             case .active:
+                #if targetEnvironment(macCatalyst)
+                SybilMacQuickQuestionController.shared.attach(viewModel)
+                #endif
                 viewModel.markAppActiveForNetwork()
                 guard shouldRefreshOnForeground, horizontalSizeClass != .compact else {
                     return
@@ -151,8 +159,13 @@ public struct SplitView: View {
         }
 
         hasPendingQuickQuestionPresentation = false
+        #if targetEnvironment(macCatalyst)
+        SybilMacQuickQuestionController.shared.attach(viewModel)
+        SybilMacQuickQuestionController.shared.show()
+        #else
         quickQuestionFocusRequest += 1
         isQuickQuestionPresented = true
+        #endif
     }
 
     private func handleQuickQuestionDismissed() {
@@ -161,23 +174,57 @@ public struct SplitView: View {
 }
 
 public struct SybilCommands: Commands {
+    public static let workspaceWindowID = "sybil-workspace"
+
     @FocusedValue(\.sybilKeyboardActions) private var keyboardActions
+    #if targetEnvironment(macCatalyst)
+    @Environment(\.openWindow) private var openWindow
+    @ObservedObject private var windowCommands = SybilMacWindowCommands.shared
+    #endif
 
     public init() {}
 
     public var body: some Commands {
         CommandGroup(replacing: .newItem) {
             Button("New Chat") {
+                #if targetEnvironment(macCatalyst)
+                windowCommands.newChatOrWindow(
+                    newChat: keyboardActions?.newChat,
+                    openWindow: openNewWindow
+                )
+                #else
                 keyboardActions?.newChat()
+                #endif
             }
             .keyboardShortcut("n", modifiers: .command)
+            #if targetEnvironment(macCatalyst)
+            .disabled(!windowCommands.canStartNewChat(hasFocusedActions: keyboardActions != nil))
+            #else
             .disabled(keyboardActions == nil)
+            #endif
+
+            #if targetEnvironment(macCatalyst)
+            Button("New Window", action: openNewWindow)
+                .keyboardShortcut("n", modifiers: [.command, .shift])
+            #endif
 
             Button("New Search") {
                 keyboardActions?.newSearch()
             }
+            #if targetEnvironment(macCatalyst)
+            .keyboardShortcut("n", modifiers: [.command, .option])
+            #else
             .keyboardShortcut("n", modifiers: [.command, .shift])
+            #endif
             .disabled(keyboardActions == nil)
+
+            #if targetEnvironment(macCatalyst)
+            Divider()
+            Button("Quick Question") {
+                SybilMacQuickQuestionController.shared.toggle()
+            }
+            .keyboardShortcut(.space, modifiers: .option)
+            #endif
         }
 
         CommandMenu("Conversation") {
@@ -194,6 +241,13 @@ public struct SybilCommands: Commands {
             .disabled(keyboardActions == nil)
         }
     }
+    #if targetEnvironment(macCatalyst)
+    private func openNewWindow() {
+        // Targeting a WindowGroup without a value creates a fresh scene every
+        // time, even when another workspace window is already open.
+        openWindow(id: Self.workspaceWindowID)
+    }
+    #endif
 }
 
 private struct SybilKeyboardActions {