feat(demo): add isolated demo environments

apps/users/migrations/0004_user_demo_fields.py

@@ -0,0 +1,25 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("users", "0003_normalize_user_email_identity"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="user",
+            name="demo_expires_at",
+            field=models.DateTimeField(blank=True, null=True),
+        ),
+        migrations.AddField(
+            model_name="user",
+            name="is_demo",
+            field=models.BooleanField(default=False),
+        ),
+        migrations.AddIndex(
+            model_name="user",
+            index=models.Index(fields=["is_demo", "demo_expires_at"], name="user_demo_expires_idx"),
+        ),
+    ]