fix: create home page as child of root in Wagtail initial data setup

_setup_wagtail_initial_data was only creating the root page (depth=1).
The page explorer shows children of root, so without a home page (depth=2)
the explorer shows 0 pages. Also update the default site to point to the
home page rather than the treebeard root.

Author: aclark4life

src/dbx_python_cli/commands/project.py

@@ -839,9 +839,10 @@ def _setup_wagtail_initial_data(
         "        locale, _ = Locale.objects.get_or_create(language_code=lang)",
         "        ct, _ = ContentType.objects.get_or_create(app_label='wagtailcore', model='page')",
         "        root = Page.add_root(title='Root', slug='root', content_type=ct, locale=locale)",
+        "        home = root.add_child(title='Home', slug='home', content_type=ct, locale=locale)",
         "        print('wagtail_root_created')",
         "        if not Site.objects.exists():",
-        "            Site.objects.create(hostname='localhost', root_page=root, is_default_site=True)",
+        "            Site.objects.create(hostname='localhost', root_page=home, is_default_site=True)",
         "            print('wagtail_site_created')",
         "except ImportError:",
         "    pass",