some changes on product stat model & signals

apps/pos_device/migrations/0019_alter_deviceactivationcode_expires_at.py

@@ -0,0 +1,19 @@
+# Generated by Django 5.0 on 2025-08-02 11:03
+
+import datetime
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pos_device', '0018_alter_deviceactivationcode_expires_at'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='deviceactivationcode',
+            name='expires_at',
+            field=models.DateTimeField(default=datetime.datetime(2025, 8, 2, 14, 33, 27, 93490)),
+        ),
+    ]