Add Daily Digest notification preferences with custom time support

- Add dailyDigest and dailyDigestHour fields to Kotlin NotificationPreference model
- Update NotificationPreferencesViewModel to support new fields
- Add Daily Summary toggle with time picker to Android NotificationPreferencesScreen
- Add Daily Summary toggle with time picker to iOS NotificationPreferencesView
- Add localized strings for Daily Summary in all 10 languages

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

composeApp/src/commonMain/kotlin/com/example/casera/ui/screens/NotificationPreferencesScreen.kt

@@ -37,20 +37,24 @@ fun NotificationPreferencesScreen(
     var taskAssigned by remember { mutableStateOf(true) }
     var residenceShared by remember { mutableStateOf(true) }
     var warrantyExpiring by remember { mutableStateOf(true) }
+    var dailyDigest by remember { mutableStateOf(true) }
     var emailTaskCompleted by remember { mutableStateOf(true) }
 
     // Custom notification times (local hours)
     var taskDueSoonHour by remember { mutableStateOf<Int?>(null) }
     var taskOverdueHour by remember { mutableStateOf<Int?>(null) }
     var warrantyExpiringHour by remember { mutableStateOf<Int?>(null) }
+    var dailyDigestHour by remember { mutableStateOf<Int?>(null) }
 
     // Time picker dialog states
     var showTaskDueSoonTimePicker by remember { mutableStateOf(false) }
     var showTaskOverdueTimePicker by remember { mutableStateOf(false) }
+    var showDailyDigestTimePicker by remember { mutableStateOf(false) }
 
     // Default local hours when user first enables custom time
     val defaultTaskDueSoonLocalHour = 14  // 2 PM local
     val defaultTaskOverdueLocalHour = 9   // 9 AM local
+    val defaultDailyDigestLocalHour = 8   // 8 AM local
 
     // Load preferences on first render
     LaunchedEffect(Unit) {
@@ -67,6 +71,7 @@ fun NotificationPreferencesScreen(
             taskAssigned = prefs.taskAssigned
             residenceShared = prefs.residenceShared
             warrantyExpiring = prefs.warrantyExpiring
+            dailyDigest = prefs.dailyDigest
             emailTaskCompleted = prefs.emailTaskCompleted
 
             // Load custom notification times (convert from UTC to local)
@@ -79,6 +84,9 @@ fun NotificationPreferencesScreen(
             prefs.warrantyExpiringHour?.let { utcHour ->
                 warrantyExpiringHour = DateUtils.utcHourToLocal(utcHour)
             }
+            prefs.dailyDigestHour?.let { utcHour ->
+                dailyDigestHour = DateUtils.utcHourToLocal(utcHour)
+            }
         }
     }
 
@@ -374,9 +382,54 @@ fun NotificationPreferencesScreen(
                                     viewModel.updatePreference(warrantyExpiring = it)
                                 }
                             )
+
+                            HorizontalDivider(
+                                modifier = Modifier.padding(horizontal = AppSpacing.lg),
+                                color = MaterialTheme.colorScheme.outline.copy(alpha = 0.3f)
+                            )
+
+                            NotificationToggle(
+                                title = stringResource(Res.string.notifications_daily_digest),
+                                description = stringResource(Res.string.notifications_daily_digest_desc),
+                                icon = Icons.Default.Summarize,
+                                iconTint = MaterialTheme.colorScheme.secondary,
+                                checked = dailyDigest,
+                                onCheckedChange = {
+                                    dailyDigest = it
+                                    viewModel.updatePreference(dailyDigest = it)
+                                }
+                            )
+
+                            // Time picker for Daily Digest
+                            if (dailyDigest) {
+                                NotificationTimePickerRow(
+                                    currentHour = dailyDigestHour,
+                                    onSetCustomTime = {
+                                        val localHour = defaultDailyDigestLocalHour
+                                        dailyDigestHour = localHour
+                                        val utcHour = DateUtils.localHourToUtc(localHour)
+                                        viewModel.updatePreference(dailyDigestHour = utcHour)
+                                    },
+                                    onChangeTime = { showDailyDigestTimePicker = true }
+                                )
+                            }
                         }
                     }
 
+                    // Daily Digest time picker dialog
+                    if (showDailyDigestTimePicker) {
+                        HourPickerDialog(
+                            currentHour = dailyDigestHour ?: defaultDailyDigestLocalHour,
+                            onHourSelected = { hour ->
+                                dailyDigestHour = hour
+                                val utcHour = DateUtils.localHourToUtc(hour)
+                                viewModel.updatePreference(dailyDigestHour = utcHour)
+                                showDailyDigestTimePicker = false
+                            },
+                            onDismiss = { showDailyDigestTimePicker = false }
+                        )
+                    }
+
                     // Email Notifications Section
                     Text(
                         stringResource(Res.string.notifications_email_section),