feat: wire ContentView router, macOS 3-column layout, scene lifecycle lock

Completes Phase 4 (Task 17) -- ContentView now routes between UnlockView
and the vault UI (NavigationStack on iOS, 3-column NavigationSplitView on
macOS) instead of the leftover SwiftData template, finally resolving the
long-standing "cannot find type Item" build break. Vault locks on
scene-background (iOS) / resign-active (macOS).

Fixes two more real bugs surfaced now that everything actually links
together: EntryEditViewModel.save's dismiss closure needed @escaping
(used inside Task {}), and UnlockView's UTType(filenameExtension:)
needed `import UniformTypeIdentifiers`.

Also restores MyPass.entitlements, which had regressed to an empty
App Group array with Keychain Sharing missing entirely since the
"wire up AutoFill extension target" commit -- likely clobbered by
Xcode reconciling capabilities at some point without a rebuild in
between to catch it. Verified clean `xcodebuild` on both iOS Simulator
and macOS destinations, and `swift test` still passes all 18 tests.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WYqycDFsynHH9VnnK7LNSf

MyPass/ContentView.swift

@@ -6,75 +6,128 @@
 //
 
 import SwiftUI
-import SwiftData
+import MyPassCore
+#if os(macOS)
+import AppKit
+#endif
 
 struct ContentView: View {
-    @Environment(\.modelContext) private var modelContext
-    @Query private var items: [Item]
+    @StateObject private var session = VaultSession()
 
     var body: some View {
-        NavigationViewWrapper {
-            List {
-                ForEach(items) { item in
-                    NavigationLink {
-                        Text("Item at \(item.timestamp, format: Date.FormatStyle(date: .numeric, time: .standard))")
-                    } label: {
-                        Text(item.timestamp, format: Date.FormatStyle(date: .numeric, time: .standard))
+        SwiftUI.Group {
+            if session.isLocked {
+                UnlockView(vm: UnlockViewModel(session: session))
+            } else {
+                vaultView
             }
         }
-                .onDelete(perform: deleteItems)
+        .onReceive(
+            NotificationCenter.default.publisher(for: sceneBackgroundNotification)
+        ) { _ in
+            session.lock()
         }
+    }
+
+    @ViewBuilder
+    private var vaultView: some View {
+        let vaultVM = VaultViewModel(session: session)
         #if os(macOS)
-            .navigationSplitViewColumnWidth(min: 180, ideal: 200)
-#endif
-            .toolbar {
-#if os(iOS)
-                ToolbarItem(placement: .navigationBarTrailing) {
-                    EditButton()
-                }
-#endif
-                ToolbarItem {
-                    Button(action: addItem) {
-                        Label("Add Item", systemImage: "plus")
-                    }
-                }
-            }
-        }
-    }
-
-    private func addItem() {
-        withAnimation {
-            let newItem = Item(timestamp: Date())
-            modelContext.insert(newItem)
-        }
-    }
-
-    private func deleteItems(offsets: IndexSet) {
-        withAnimation {
-            for index in offsets {
-                modelContext.delete(items[index])
-            }
-        }
-    }
-}
-
-fileprivate struct NavigationViewWrapper<Content: View>: View {
-    let content: () -> Content
-
-    var body: some View {
-#if os(macOS)
-        NavigationSplitView {
-            content()
-        } detail: {
-            Text("Select an item")
-        }
+        MacVaultView(vm: vaultVM)
         #else
-        content()
+        NavigationStack {
+            if let root = session.database?.root {
+                GroupBrowserView(vm: vaultVM, group: root)
+            }
+        }
+        #endif
+    }
+
+    private var sceneBackgroundNotification: Notification.Name {
+        #if os(iOS)
+        UIScene.didEnterBackgroundNotification
+        #else
+        NSApplication.didResignActiveNotification
         #endif
     }
 }
 
-#Preview {
-    ContentView()
-        .modelContainer(for: Item.self, inMemory: true)
+// MARK: - macOS 3-column layout
+
+#if os(macOS)
+private struct MacVaultView: View {
+    @ObservedObject var vm: VaultViewModel
+    @State private var selectedGroup: MyPassCore.Group?
+    @State private var selectedEntry: Entry?
+    @State private var showAddEntry = false
+
+    private var activeGroup: MyPassCore.Group? { selectedGroup ?? vm.session.database?.root }
+
+    var body: some View {
+        NavigationSplitView {
+            GroupSidebarView(vm: vm, selectedGroup: $selectedGroup)
+        } content: {
+            if vm.isSearching {
+                SearchView(vm: vm, selectedEntry: $selectedEntry)
+            } else if let group = activeGroup {
+                entryList(for: group)
+            } else {
+                Text("Select a group").foregroundStyle(.secondary)
             }
+        } detail: {
+            if let entry = selectedEntry {
+                EntryDetailView(entry: entry, session: vm.session)
+            } else {
+                Text("Select an entry").foregroundStyle(.secondary)
+            }
+        }
+        .searchable(text: $vm.searchQuery, prompt: "Search all entries…")
+        .sheet(isPresented: $showAddEntry) {
+            if let group = activeGroup {
+                EntryEditView(vm: EntryEditViewModel(session: vm.session, groupId: group.id))
+            }
+        }
+    }
+
+    private func entryList(for group: MyPassCore.Group) -> some View {
+        List(group.entries, selection: $selectedEntry) { entry in
+            EntryListRow(entry: entry).tag(entry)
+        }
+        .navigationTitle(group.name)
+        .toolbar {
+            ToolbarItem {
+                Button { showAddEntry = true } label: { Image(systemName: "plus") }
+            }
+        }
+    }
+}
+
+private struct GroupSidebarView: View {
+    @ObservedObject var vm: VaultViewModel
+    @Binding var selectedGroup: MyPassCore.Group?
+
+    var body: some View {
+        List(selection: $selectedGroup) {
+            if let root = vm.session.database?.root {
+                GroupNode(group: root)
+            }
+        }
+        .navigationTitle("Groups")
+    }
+}
+
+private struct GroupNode: View {
+    let group: MyPassCore.Group
+    var body: some View {
+        if group.subgroups.isEmpty {
+            Label(group.name, systemImage: "folder").tag(group)
+        } else {
+            DisclosureGroup {
+                ForEach(group.subgroups) { sub in GroupNode(group: sub) }
+            } label: {
+                Label(group.name, systemImage: "folder").tag(group)
+            }
+        }
+    }
+}
+#endif

MyPass/MyPass.entitlements

@@ -3,6 +3,12 @@
 <plist version="1.0">
 <dict>
 	<key>com.apple.security.application-groups</key>
-	<array/>
+	<array>
+		<string>group.org.antiloop222.mypass</string>
+	</array>
+	<key>keychain-access-groups</key>
+	<array>
+		<string>$(AppIdentifierPrefix)org.antiloop222.mypass</string>
+	</array>
 </dict>
 </plist>

MyPass/ViewModels/EntryEditViewModel.swift

@@ -39,7 +39,7 @@ final class EntryEditViewModel: ObservableObject {
 
     var isEditing: Bool { existingEntry != nil }
 
-    func save(dismiss: () -> Void) {
+    func save(dismiss: @escaping () -> Void) {
         Task {
             isSaving = true
             errorMessage = nil

MyPass/Views/UnlockView.swift

@@ -4,6 +4,7 @@
 //
 
 import SwiftUI
+import UniformTypeIdentifiers
 import MyPassCore
 
 struct UnlockView: View {