Add read-only admin functionality and enhance billing models in admin interface

backend/igny8_core/business/publishing/admin.py

@@ -0,0 +1,36 @@
+from django.contrib import admin
+from igny8_core.admin.base import SiteSectorAdminMixin
+from .models import PublishingRecord, DeploymentRecord
+
+
+@admin.register(PublishingRecord)
+class PublishingRecordAdmin(SiteSectorAdminMixin, admin.ModelAdmin):
+    list_display = [
+        'content',
+        'site',
+        'sector',
+        'destination',
+        'status',
+        'destination_url',
+        'published_at',
+    ]
+    list_filter = ['destination', 'status', 'site']
+    search_fields = ['content__title', 'destination', 'destination_url']
+    readonly_fields = ['created_at', 'updated_at']
+
+
+@admin.register(DeploymentRecord)
+class DeploymentRecordAdmin(SiteSectorAdminMixin, admin.ModelAdmin):
+    list_display = [
+        'site',
+        'sector',
+        'version',
+        'deployed_version',
+        'status',
+        'deployment_url',
+        'deployed_at',
+    ]
+    list_filter = ['status', 'site']
+    search_fields = ['site__name', 'deployment_url']
+    readonly_fields = ['created_at', 'updated_at']
+