🚩(backend) add homepage feature flag

Add a homepage feature flag that we will
propagate to the frontend.
It will be used to enable or disable the
homepage at runtime.

src/backend/core/api/viewsets.py

@@ -1692,6 +1692,7 @@ class ConfigView(drf.views.APIView):
             "CRISP_WEBSITE_ID",
             "ENVIRONMENT",
             "FRONTEND_CSS_URL",
+            "FRONTEND_HOMEPAGE_FEATURE_ENABLED",
             "FRONTEND_FOOTER_FEATURE_ENABLED",
             "FRONTEND_THEME",
             "MEDIA_BASE_URL",

src/backend/core/tests/test_api_config.py

@@ -19,6 +19,7 @@ pytestmark = pytest.mark.django_db
     COLLABORATION_WS_URL="http://testcollab/",
     CRISP_WEBSITE_ID="123",
     FRONTEND_CSS_URL="http://testcss/",
+    FRONTEND_HOMEPAGE_FEATURE_ENABLED=True,
     FRONTEND_FOOTER_FEATURE_ENABLED=True,
     FRONTEND_THEME="test-theme",
     MEDIA_BASE_URL="http://testserver/",
@@ -41,6 +42,7 @@ def test_api_config(is_authenticated):
         "CRISP_WEBSITE_ID": "123",
         "ENVIRONMENT": "test",
         "FRONTEND_CSS_URL": "http://testcss/",
+        "FRONTEND_HOMEPAGE_FEATURE_ENABLED": True,
         "FRONTEND_FOOTER_FEATURE_ENABLED": True,
         "FRONTEND_THEME": "test-theme",
         "LANGUAGES": [