Add Organization and User serializers to device viewset for enhanced user data retrieval

apps/pos_device/pos/api/v1/serializers/user.py

@@ -0,0 +1,8 @@
+from django.contrib.auth.models import User as pos_models
+from rest_framework import serializers
+
+
+class UserSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = pos_models.User
+        fields = ['id', 'username', 'first_name', 'last_name', 'email', 'mobile', 'phone', 'national_code']