fix: address AutoFill extension code review findings

- Remove dead provideCredentialWithoutUserInteraction override and
  unlockSilently() helper (nothing registers credential identities,
  so it could never run, and it was a footgun for future inline
  QuickType work).
- Surface non-cancellation biometric unlock failures into
  errorMessage instead of swallowing them, matching
  UnlockViewModel.unlockWithBiometrics().
- Forward VaultSession.objectWillChange into ExtensionViewModel via
  Combine so the lock/unlock UI transition no longer depends on an
  accidental isUnlocking side effect, matching VaultViewModel's
  pattern.
- Show the "Open MyPass" deep-link escape hatch whenever unlock
  fails (errorMessage set), not only when there's no bookmark yet,
  per the extension constraints spec.
- Add INFOPLIST_KEY_NSFaceIDUsageDescription to the MyPass and
  AutoFill targets' Debug/Release build configs.

Also folds in pre-existing alphabetical reordering of two
PBXBuildFile/PBXFileReference entries in project.pbxproj from an
earlier task, since this same file is already being touched here.

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

AutoFill/Views/ExtensionUnlockView.swift

@@ -73,7 +73,7 @@ struct ExtensionRootView: View {
                 Text(msg).foregroundStyle(.red).font(.caption).multilineTextAlignment(.center)
             }
 
-            if !vm.hasVault {
+            if !vm.hasVault || vm.errorMessage != nil {
                 Link(destination: URL(string: "mypass://unlock")!) {
                     Label("Open MyPass to set up vault", systemImage: "arrow.up.right")
                         .font(.caption)
@@ -98,6 +98,7 @@ final class ExtensionViewModel: ObservableObject {
     private let biometricService: BiometricAuthService
     private let onSelect: (Entry) -> Void
     private let onCancel: () -> Void
+    private var sessionCancellable: AnyCancellable?
 
     init(
         session: VaultSession,
@@ -115,6 +116,9 @@ final class ExtensionViewModel: ObservableObject {
         self.biometricService = biometricService
         self.onSelect = onSelect
         self.onCancel = onCancel
+        sessionCancellable = session.objectWillChange.sink { [weak self] in
+            self?.objectWillChange.send()
+        }
     }
 
     var isLocked: Bool { session.isLocked }
@@ -139,7 +143,7 @@ final class ExtensionViewModel: ObservableObject {
             try await biometricService.authenticate(reason: "Unlock MyPass")
             try performUnlockFromKeychain()
         } catch {
-            // Silently fail -- user can type password
+            errorMessage = error.localizedDescription
         }
         isUnlocking = false
     }