Address PR review feedback

- Gate e2e-admin superuser behind E2E_MODE env var (security)
- Add status and tag filters to ArticleFilterSet
- Set default_ordering to -published_date on listing viewset
- Add summary to ArticlePage.search_fields for search support
- Add 4 new tests for filters, ordering, and search fields

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

apps/blog/models.py

@@ -15,6 +15,7 @@ from wagtail.admin.panels import FieldPanel, ObjectList, PageChooserPanel, Tabbe
 from wagtail.contrib.routable_page.models import RoutablePageMixin, route
 from wagtail.fields import RichTextField, StreamField
 from wagtail.models import Page
+from wagtail.search import index
 from wagtailseo.models import SeoMixin
 
 from apps.blog.blocks import ARTICLE_BODY_BLOCKS
@@ -232,7 +233,9 @@ class ArticlePage(SeoMixin, Page):
         ]
     )
 
-    search_fields = Page.search_fields
+    search_fields = Page.search_fields + [
+        index.SearchField("summary"),
+    ]
 
     def save(self, *args: Any, **kwargs: Any) -> None:
         if not self.category_id: