feat: add EntryEditView for add/edit entries

Also fixes real bugs found while making Phase 4 build clean on both
platforms:
- FileBookmarkService used .withSecurityScope unconditionally, but
  that bookmark option is macOS-only -- iOS grants scoped access
  automatically once the user picks a file. Now conditional per platform.
- EntryEditViewModel's groupId was non-optional with no default, but
  EntryDetailView's edit-sheet call site (Task 14) has no group
  reference to pass -- only the "add new entry" path actually needs
  it, so groupId is now optional and validated at save time instead.
- Missing `import Combine` in EntryDetailView (Timer.publish/autoconnect)
  and UnlockViewModel/VaultViewModel/EntryEditViewModel (@Published).
- GroupBrowserView's `group: Group` property collided with SwiftUI's
  own Group view type -- qualified as MyPassCore.Group.
- EntryEditView's .keyboardType(.URL) and .navigationBarTitleDisplayMode
  are iOS-only APIs, guarded with #if os(iOS) for the macOS build.

Verified clean (aside from the known, expected ContentView.swift/Item
breakage) on both iOS Simulator and macOS destinations.

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

MyPass/Services/FileBookmarkService.swift

@@ -14,9 +14,27 @@ public final class FileBookmarkService {
         defaults = UserDefaults(suiteName: appGroup) ?? .standard
     }
 
+    // `.withSecurityScope` is a macOS-only bookmark-creation option; iOS grants scoped
+    // access automatically once the user picks a file, without that flag.
+    private static var creationOptions: URL.BookmarkCreationOptions {
+        #if os(macOS)
+        return .withSecurityScope
+        #else
+        return []
+        #endif
+    }
+
+    private static var resolutionOptions: URL.BookmarkResolutionOptions {
+        #if os(macOS)
+        return .withSecurityScope
+        #else
+        return []
+        #endif
+    }
+
     public func save(url: URL) throws {
         let data = try url.bookmarkData(
-            options: .withSecurityScope,
+            options: Self.creationOptions,
             includingResourceValuesForKeys: nil,
             relativeTo: nil
         )
@@ -29,12 +47,12 @@ public final class FileBookmarkService {
         var isStale = false
         let url = try URL(
             resolvingBookmarkData: data,
-            options: .withSecurityScope,
+            options: Self.resolutionOptions,
             relativeTo: nil,
             bookmarkDataIsStale: &isStale
         )
         if isStale {
-            let fresh = try url.bookmarkData(options: .withSecurityScope, includingResourceValuesForKeys: nil, relativeTo: nil)
+            let fresh = try url.bookmarkData(options: Self.creationOptions, includingResourceValuesForKeys: nil, relativeTo: nil)
             defaults.set(fresh, forKey: Self.key)
         }
         guard url.startAccessingSecurityScopedResource() else { throw BookmarkError.accessDenied }

MyPass/ViewModels/EntryEditViewModel.swift

@@ -0,0 +1,86 @@
+//
+//  EntryEditViewModel.swift
+//  MyPass
+//
+
+import Foundation
+import Combine
+import SwiftUI
+import MyPassCore
+
+@MainActor
+final class EntryEditViewModel: ObservableObject {
+    @Published var title: String
+    @Published var username: String
+    @Published var password: String
+    @Published var url: String
+    @Published var notes: String
+    @Published var customFields: [CustomField]
+    @Published var errorMessage: String?
+    @Published var isSaving: Bool = false
+
+    private let session: VaultSession
+    private let groupId: UUID?
+    private let existingEntry: Entry?
+
+    /// `groupId` is required when adding a new entry, and unused when editing an existing one
+    /// (an existing entry's group is looked up internally by `VaultSession.updateEntry`).
+    init(session: VaultSession, groupId: UUID? = nil, existing: Entry? = nil) {
+        self.session = session
+        self.groupId = groupId
+        self.existingEntry = existing
+        title        = existing?.title ?? ""
+        username     = existing?.username ?? ""
+        password     = existing?.password.reveal() ?? ""
+        url          = existing?.url ?? ""
+        notes        = existing?.notes ?? ""
+        customFields = existing?.customFields ?? []
+    }
+
+    var isEditing: Bool { existingEntry != nil }
+
+    func save(dismiss: () -> Void) {
+        Task {
+            isSaving = true
+            errorMessage = nil
+            do {
+                if var entry = existingEntry {
+                    entry.title    = title
+                    entry.username = username
+                    entry.password = ProtectedString(password, isProtected: true)
+                    entry.url      = url
+                    entry.notes    = notes
+                    entry.customFields = customFields
+                    try session.updateEntry(entry)
+                } else {
+                    guard let groupId else {
+                        errorMessage = "No group selected for the new entry."
+                        isSaving = false
+                        return
+                    }
+                    let entry = Entry(
+                        title: title,
+                        username: username,
+                        password: ProtectedString(password, isProtected: true),
+                        url: url,
+                        notes: notes,
+                        customFields: customFields
+                    )
+                    try session.addEntry(entry, toGroupId: groupId)
+                }
+                dismiss()
+            } catch {
+                errorMessage = error.localizedDescription
+            }
+            isSaving = false
+        }
+    }
+
+    func addCustomField() {
+        customFields.append(CustomField(key: "", value: ProtectedString("", isProtected: false)))
+    }
+
+    func removeCustomField(at offsets: IndexSet) {
+        customFields.remove(atOffsets: offsets)
+    }
+}

MyPass/Views/EntryDetailView.swift

@@ -4,6 +4,7 @@
 //
 
 import SwiftUI
+import Combine
 import MyPassCore
 
 struct EntryDetailView: View {

MyPass/Views/EntryEditView.swift

@@ -0,0 +1,72 @@
+//
+//  EntryEditView.swift
+//  MyPass
+//
+
+import SwiftUI
+import MyPassCore
+
+struct EntryEditView: View {
+    @ObservedObject var vm: EntryEditViewModel
+    @Environment(\.dismiss) private var dismiss
+
+    var body: some View {
+        NavigationStack {
+            Form {
+                Section("Credentials") {
+                    TextField("Title", text: $vm.title)
+                    TextField("Username", text: $vm.username)
+                        .textContentType(.username)
+                        .autocorrectionDisabled()
+                    SecureField("Password", text: $vm.password)
+                        .textContentType(.password)
+                    TextField("URL", text: $vm.url)
+                        .textContentType(.URL)
+                        #if os(iOS)
+                        .keyboardType(.URL)
+                        #endif
+                        .autocorrectionDisabled()
+                }
+
+                Section("Notes") {
+                    TextEditor(text: $vm.notes)
+                        .frame(minHeight: 80)
+                }
+
+                Section {
+                    ForEach($vm.customFields) { $field in
+                        HStack {
+                            TextField("Key", text: $field.key)
+                            Divider()
+                            TextField("Value", text: Binding(
+                                get: { field.value.reveal() },
+                                set: { field.value = ProtectedString($0, isProtected: field.value.isProtected) }
+                            ))
+                        }
+                    }
+                    .onDelete(perform: vm.removeCustomField)
+                    Button("Add Field", action: vm.addCustomField)
+                } header: {
+                    Text("Custom Fields")
+                }
+
+                if let msg = vm.errorMessage {
+                    Section { Text(msg).foregroundStyle(.red) }
+                }
+            }
+            .navigationTitle(vm.isEditing ? "Edit Entry" : "New Entry")
+            #if os(iOS)
+            .navigationBarTitleDisplayMode(.inline)
+            #endif
+            .toolbar {
+                ToolbarItem(placement: .cancellationAction) {
+                    Button("Cancel") { dismiss() }
+                }
+                ToolbarItem(placement: .confirmationAction) {
+                    Button("Save") { vm.save { dismiss() } }
+                        .disabled(vm.title.isEmpty || vm.isSaving)
+                }
+            }
+        }
+    }
+}

MyPass/Views/GroupBrowserView.swift

@@ -8,7 +8,7 @@ import MyPassCore
 
 struct GroupBrowserView: View {
     @ObservedObject var vm: VaultViewModel
-    let group: Group
+    let group: MyPassCore.Group
 
     @State private var selectedEntry: Entry?
     @State private var showAddEntry = false