✨(api) add CRUD for mailbox manager MailDomain models

Add create,list,retrieve and delete actions for MailDomain model.

src/backend/mailbox_manager/migrations/0002_alter_maildomainaccess_domain.py

@@ -0,0 +1,19 @@
+# Generated by Django 5.0.3 on 2024-04-17 11:58
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('mailbox_manager', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='maildomainaccess',
+            name='domain',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='accesses', to='mailbox_manager.maildomain'),
+        ),
+    ]