Add wallet balance to User model and implement Atoll/Island management

- Added `wallet_balance` field to the User model.
- Updated UserAdmin to include `wallet_balance` in the admin interface.
- Created serializers and views for Atoll and Island management.
- Implemented endpoints for listing, creating, and updating Atolls and Islands.
- Enhanced payment processing with UUIDs for Payment and Topup models.
- Added migration files for new fields and constraints.
- Improved error handling and validation in various views.
- Updated email templates for better responsiveness and SEO.

api/migrations/0005_alter_atoll_name_alter_island_name.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.1.2 on 2025-01-20 14:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("api", "0004_alter_atoll_id_alter_island_id"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="atoll",
+            name="name",
+            field=models.CharField(max_length=255, unique=True),
+        ),
+        migrations.AlterField(
+            model_name="island",
+            name="name",
+            field=models.CharField(max_length=255, unique=True),
+        ),
+    ]