Refactor code structure and remove redundant changes

django-backend/apps/timeline/admin.py

@@ -0,0 +1,33 @@
+from django.contrib import admin
+from unfold.admin import ModelAdmin
+from .models import EntityTimelineEvent
+
+
+@admin.register(EntityTimelineEvent)
+class EntityTimelineEventAdmin(ModelAdmin):
+    list_display = ['title', 'entity_type', 'entity_id', 'event_type', 'event_date', 'is_public', 'created_by']
+    list_filter = ['entity_type', 'event_type', 'is_public', 'event_date', 'event_date_precision']
+    search_fields = ['title', 'description', 'entity_id']
+    date_hierarchy = 'event_date'
+    ordering = ['-event_date', '-created_at']
+    readonly_fields = ['created_at', 'updated_at']
+    
+    fieldsets = (
+        ('Event Information', {
+            'fields': ('title', 'description', 'event_type', 'event_date', 'event_date_precision')
+        }),
+        ('Entity Reference', {
+            'fields': ('entity_type', 'entity_id')
+        }),
+        ('Event Details', {
+            'fields': ('from_entity_id', 'to_entity_id', 'from_location', 'to_location', 'from_value', 'to_value'),
+            'classes': ('collapse',)
+        }),
+        ('Visibility & Order', {
+            'fields': ('is_public', 'display_order')
+        }),
+        ('Tracking', {
+            'fields': ('created_by', 'approved_by', 'submission', 'created_at', 'updated_at'),
+            'classes': ('collapse',)
+        }),
+    )