django admin improvement complete

backend/igny8_core/business/billing/models.py

@@ -6,6 +6,7 @@ from django.db import models
 from django.core.validators import MinValueValidator
 from django.conf import settings
 from igny8_core.auth.models import AccountBaseModel
+from simple_history.models import HistoricalRecords
 
 
 # Centralized payment method choices - single source of truth
@@ -167,6 +168,9 @@ class CreditCostConfig(models.Model):
         help_text="Cost before last update (for audit trail)"
     )
     
+    # History tracking
+    history = HistoricalRecords()
+    
     class Meta:
         app_label = 'billing'
         db_table = 'igny8_credit_cost_config'
@@ -459,6 +463,9 @@ class Payment(AccountBaseModel):
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
     
+    # History tracking
+    history = HistoricalRecords()
+    
     class Meta:
         app_label = 'billing'
         db_table = 'igny8_payments'