fix(backup): drop the duplicate start-backup row under its own hero

With nothing backed up, the hero already renders START BACKUP as its
primary action, so the identical menu row a few pixels below it was pure
noise. The row is suppressed in that one state and stays in every other
one, where the hero offers a different action or none at all.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: FrancisPouliot

lib/features/backup_settings/ui/screens/backup_settings_screen.dart

@@ -146,15 +146,29 @@ class _Screen extends StatelessWidget {
   List<Widget> _menuRows(BackupSettingsState state) => [
     // Availability is not encouragement. The hero never asks for another
     // backup once a physical one is fresh, but adding one deliberately has to
-    // stay possible from here in every state.
-    const _StartBackupButton(),
+    // stay possible from here in every state — EXCEPT the one state where the
+    // hero is already offering this exact action, where a second identical
+    // entry a few pixels below it is just noise.
+    if (!_heroOffersStartBackup(state)) const _StartBackupButton(),
     if (state.lastEncryptedBackup != null) const _ViewVaultKeyButton(),
     if (state.lastEncryptedBackup != null || state.lastPhysicalBackup != null)
       const _TestBackupButton(),
     const _EncryptedVaultSettingsButton(),
     const _Bip329LabelsButton(),
     const _TransactionHistoryButton(),
   ];
+
+  /// True only in the zero-backup state, where [_ZeroBackupHero] already
+  /// renders START BACKUP as its primary action. Mirrors the `posture == null`
+  /// branch of [_hero]; every other state either shows a different hero action
+  /// or none at all, so the menu row stays.
+  bool _heroOffersStartBackup(BackupSettingsState state) =>
+      state.status == BackupSettingsStatus.success &&
+      BackupHealthPosture.of(
+            isEncryptedVaultTested: state.isDefaultEncryptedBackupTested,
+            isPhysicalBackupTested: state.isDefaultPhysicalBackupTested,
+          ) ==
+          null;
 }
 
 class _StatusRow extends StatelessWidget {

test/features/backup_settings/ui/backup_settings_screen_test.dart

@@ -161,8 +161,10 @@ void main() {
   // backup is fresh, but adding another backup must never stop being possible.
   group('the backup action is always available', () {
     final now = DateTime.now();
+    // The zero-backup state is deliberately absent: there the hero itself
+    // renders START BACKUP, so the menu row would be a second identical entry
+    // a few pixels below it. Covered by its own test after this group.
     final postures = <String, Map<String, Object?>>{
-      'nothing backed up': {'physical': false, 'vault': false},
       'vault only': {'physical': false, 'vault': true, 'vaultAt': now},
       'physical fresh': {
         'physical': true,
@@ -198,6 +200,18 @@ void main() {
     }
   });
 
+  testWidgets(
+    'the zero-backup hero offers START BACKUP without a duplicate menu row',
+    (tester) async {
+      await pumpScreen(tester, physicalTested: false, vaultTested: false);
+
+      // The hero's own CTA is present…
+      expect(find.text(loc.backupSettingsStartBackupAction), findsOneWidget);
+      // …and the menu row offering the same action is suppressed here only.
+      expect(find.text(loc.backupSettingsStartBackup), findsNothing);
+    },
+  );
+
   testWidgets('names the encrypted vault menu row after the status row', (
     tester,
   ) async {