Enhance moderation dashboard UI and UX:

- Add HTMX-powered filtering with instant updates
- Add smooth transitions and loading states
- Improve visual hierarchy and styling
- Add review notes functionality
- Add confirmation dialogs for actions
- Make navigation sticky
- Add hover effects and visual feedback
- Improve dark mode support

history_tracking/mixins.py

@@ -1,12 +1,30 @@
 # history_tracking/mixins.py
+from django.db import models
+from django.conf import settings
 
+class HistoricalChangeMixin(models.Model):
+    """Mixin for historical models to track changes"""
+    id = models.BigIntegerField(db_index=True, auto_created=True, blank=True)
+    history_date = models.DateTimeField()
+    history_id = models.AutoField(primary_key=True)
+    history_type = models.CharField(max_length=1)
+    history_user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        null=True,
+        on_delete=models.SET_NULL,
+        related_name='+'
+    )
+    history_change_reason = models.CharField(max_length=100, null=True)
+    
+    class Meta:
+        abstract = True
+        ordering = ['-history_date', '-history_id']
 
-class HistoricalChangeMixin:
     @property
     def prev_record(self):
         """Get the previous record for this instance"""
         try:
-            return type(self).objects.filter(
+            return self.__class__.objects.filter(
                 history_date__lt=self.history_date,
                 id=self.id
             ).order_by('-history_date').first()
@@ -28,12 +46,29 @@ class HistoricalChangeMixin:
                 "history_user_id",
                 "history_change_reason",
                 "history_type",
+                "id",
+                "_state",
+                "_history_user_cache"
             ] and not field.startswith("_"):
                 try:
                     old_value = getattr(prev_record, field)
                     new_value = getattr(self, field)
                     if old_value != new_value:
-                        changes[field] = {"old": old_value, "new": new_value}
+                        changes[field] = {"old": str(old_value), "new": str(new_value)}
                 except AttributeError:
                     continue
         return changes
+
+    @property
+    def history_user_display(self):
+        """Get a display name for the history user"""
+        if hasattr(self, 'history_user') and self.history_user:
+            return str(self.history_user)
+        return None
+
+    def get_instance(self):
+        """Get the model instance this history record represents"""
+        try:
+            return self.__class__.objects.get(id=self.id)
+        except self.__class__.DoesNotExist:
+            return None