Added sqlite

lib/models/vehicle.dart

@@ -6,6 +6,13 @@ class Vehicle {
   final String licensePlate;
   final DateTime updatedAt;
 
+  /// Soft-delete tombstone: null means active. Deleting sets this instead
+  /// of removing the row, so the deletion itself can be merged/synced like
+  /// any other change (newest `updatedAt` wins) instead of silently
+  /// disappearing and later being resurrected by a device that hasn't seen
+  /// the deletion yet.
+  final DateTime? deletedAt;
+
   Vehicle({
     required this.id,
     required this.make,
@@ -13,6 +20,7 @@ class Vehicle {
     required this.color,
     required this.licensePlate,
     required this.updatedAt,
+    this.deletedAt,
   });
 
   String get displayName => '$color $make $model ($licensePlate)';
@@ -23,6 +31,7 @@ class Vehicle {
     String? color,
     String? licensePlate,
     DateTime? updatedAt,
+    DateTime? deletedAt,
   }) {
     return Vehicle(
       id: id,
@@ -31,26 +40,29 @@ class Vehicle {
       color: color ?? this.color,
       licensePlate: licensePlate ?? this.licensePlate,
       updatedAt: updatedAt ?? this.updatedAt,
+      deletedAt: deletedAt ?? this.deletedAt,
     );
   }
 
-  Map<String, dynamic> toJson() => {
+  Map<String, Object?> toMap() => {
         'id': id,
         'make': make,
         'model': model,
         'color': color,
-        'licensePlate': licensePlate,
-        'updatedAt': updatedAt.toIso8601String(),
+        'license_plate': licensePlate,
+        'updated_at': updatedAt.millisecondsSinceEpoch,
+        'deleted_at': deletedAt?.millisecondsSinceEpoch,
       };
 
-  factory Vehicle.fromJson(Map<String, dynamic> json) => Vehicle(
-        id: json['id'] as String,
-        make: json['make'] as String,
-        model: json['model'] as String,
-        color: json['color'] as String,
-        licensePlate: json['licensePlate'] as String,
-        updatedAt: json['updatedAt'] != null
-            ? DateTime.parse(json['updatedAt'] as String)
-            : DateTime.fromMillisecondsSinceEpoch(0),
+  factory Vehicle.fromMap(Map<String, Object?> map) => Vehicle(
+        id: map['id'] as String,
+        make: map['make'] as String,
+        model: map['model'] as String,
+        color: map['color'] as String,
+        licensePlate: map['license_plate'] as String,
+        updatedAt: DateTime.fromMillisecondsSinceEpoch(map['updated_at'] as int, isUtc: true),
+        deletedAt: map['deleted_at'] != null
+            ? DateTime.fromMillisecondsSinceEpoch(map['deleted_at'] as int, isUtc: true)
+            : null,
       );
 }