refactor: Projektstruktur in app/ und backend/ aufgeteilt

app/lib/models/tasks/generic_task.dart

@@ -0,0 +1,81 @@
+import '../task.dart';
+
+// Generic Task implementation for fallback
+class GenericTask extends Task {
+  GenericTask({
+    required super.id,
+    required super.jobId,
+    super.stationOrder,
+    super.completed = false,
+    super.optional = false,
+    super.completedAt,
+    super.completedBy,
+    super.taskOrder,
+    super.title,
+    super.description,
+    super.displayName,
+  });
+
+  factory GenericTask.fromJson(Map<String, dynamic> json) {
+    final commonProps = Task.parseCommonProperties(json);
+    return GenericTask(
+      id: commonProps['id'],
+      jobId: commonProps['jobId'],
+      stationOrder: commonProps['stationOrder'],
+      completed: commonProps['completed'],
+      optional: commonProps['optional'],
+      completedAt: commonProps['completedAt'],
+      completedBy: commonProps['completedBy'],
+      taskOrder: commonProps['taskOrder'],
+      title: commonProps['title'],
+      description: commonProps['description'],
+      displayName: commonProps['displayName'],
+    );
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'jobId': jobId,
+      'stationOrder': stationOrder,
+      'completed': completed,
+      'optional': optional,
+      'completedAt': completedAt?.toIso8601String(),
+      'completedBy': completedBy,
+      'taskOrder': taskOrder,
+      'description': description,
+      'displayName': displayName,
+      'taskSpecificData': {'taskType': 'GENERIC', 'title': title},
+    };
+  }
+
+  @override
+  GenericTask copyWith({
+    String? id,
+    String? jobId,
+    int? stationOrder,
+    bool? completed,
+    bool? optional,
+    DateTime? completedAt,
+    String? completedBy,
+    int? taskOrder,
+    String? title,
+    String? description,
+    String? displayName,
+  }) {
+    return GenericTask(
+      id: id ?? this.id,
+      jobId: jobId ?? this.jobId,
+      stationOrder: stationOrder ?? this.stationOrder,
+      completed: completed ?? this.completed,
+      optional: optional ?? this.optional,
+      completedAt: completedAt ?? this.completedAt,
+      completedBy: completedBy ?? this.completedBy,
+      taskOrder: taskOrder ?? this.taskOrder,
+      title: title ?? this.title,
+      description: description ?? this.description,
+      displayName: displayName ?? this.displayName,
+    );
+  }
+}