create appointment object

Frontend/lib/mih_objects/appointment.dart

@@ -0,0 +1,39 @@
+class Appointment {
+  final int idappointments;
+  final String app_id;
+  final String business_id;
+  final String date_time;
+  final String title;
+  final String description;
+
+  const Appointment({
+    required this.idappointments,
+    required this.app_id,
+    required this.business_id,
+    required this.date_time,
+    required this.title,
+    required this.description,
+  });
+
+  factory Appointment.fromJson(Map<String, dynamic> json) {
+    return switch (json) {
+      {
+        "idappointments": int idappointments,
+        'app_id': String app_id,
+        'business_id': String business_id,
+        'date_time': String date_time,
+        'title': String title,
+        'description': String description,
+      } =>
+        Appointment(
+          idappointments: idappointments,
+          app_id: app_id,
+          business_id: business_id,
+          date_time: date_time,
+          title: title,
+          description: description,
+        ),
+      _ => throw const FormatException('Failed to load album.'),
+    };
+  }
+}