fix: update existing default site in seed command instead of hardcoding 127.0.0.1

Wagtail initialises the default site with hostname 'localhost'. The previous
get_or_create on '127.0.0.1' left the localhost site intact (still pointing
to the Welcome page), so browsers got the wrong root page.

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

apps/core/management/commands/seed_e2e_content.py

@@ -116,15 +116,12 @@ class Command(BaseCommand):
             legal_index.add_child(instance=privacy)
             privacy.save_revision().publish()
 
-        site, _ = Site.objects.get_or_create(
-            hostname="127.0.0.1",
-            port=8000,
-            defaults={
-                "root_page": home,
-                "is_default_site": True,
-                "site_name": "No Hype AI",
-            },
-        )
+        # Update the existing default site (whatever hostname Wagtail created it with)
+        # rather than creating a new 127.0.0.1 entry that leaves localhost pointing
+        # to the Welcome page.
+        site = Site.objects.filter(is_default_site=True).first()
+        if site is None:
+            site = Site(hostname="localhost", port=80)
         site.root_page = home
         site.is_default_site = True
         site.site_name = "No Hype AI"