Enhance AppSettings and RentController to manage not-occupied months, add lifetime summary to SettingsScreen, and update tests for compatibility

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

lib/models/app_settings.dart

@@ -5,6 +5,7 @@ class AppSettings {
     required this.rentUsd,
     required this.occupied,
     this.notOccupiedFromYearMonth,
+    this.notOccupiedMonths = const <String>[],
     this.localFallbackHour = 9,
     this.localQuietHourStart = 23,
   });
@@ -12,6 +13,7 @@ class AppSettings {
   final double rentUsd;
   final bool occupied;
   final String? notOccupiedFromYearMonth;
+  final List<String> notOccupiedMonths;
   final int localFallbackHour;
   final int localQuietHourStart;
 
@@ -23,6 +25,7 @@ class AppSettings {
     double? rentUsd,
     bool? occupied,
     String? notOccupiedFromYearMonth,
+    List<String>? notOccupiedMonths,
     bool clearNotOccupiedFromYearMonth = false,
     int? localFallbackHour,
     int? localQuietHourStart,
@@ -33,6 +36,7 @@ class AppSettings {
       notOccupiedFromYearMonth: clearNotOccupiedFromYearMonth
           ? null
           : (notOccupiedFromYearMonth ?? this.notOccupiedFromYearMonth),
+      notOccupiedMonths: notOccupiedMonths ?? this.notOccupiedMonths,
       localFallbackHour: localFallbackHour ?? this.localFallbackHour,
       localQuietHourStart: localQuietHourStart ?? this.localQuietHourStart,
     );
@@ -43,6 +47,7 @@ class AppSettings {
       'rentUsd': rentUsd,
       'occupied': occupied,
       'notOccupiedFromYearMonth': notOccupiedFromYearMonth,
+      'notOccupiedMonths': notOccupiedMonths,
       'localFallbackHour': localFallbackHour,
       'localQuietHourStart': localQuietHourStart,
     };
@@ -53,6 +58,10 @@ class AppSettings {
       rentUsd: (json['rentUsd'] ?? 0).toDouble(),
       occupied: json['occupied'] ?? true,
       notOccupiedFromYearMonth: json['notOccupiedFromYearMonth'] as String?,
+      notOccupiedMonths:
+          (json['notOccupiedMonths'] as List<dynamic>? ?? const <dynamic>[])
+              .whereType<String>()
+              .toList(),
       localFallbackHour: json['localFallbackHour'] ?? 9,
       localQuietHourStart: json['localQuietHourStart'] ?? 23,
     );