✨(backend) add public endpoint /api/v1.0/config/

Add public endpoint /api/v1.0/config/ to
share some public configuration values.

src/backend/core/tests/test_api_config.py

@@ -0,0 +1,47 @@
+"""
+Test config API endpoints in the Impress core app.
+"""
+
+from django.test import override_settings
+
+import pytest
+from rest_framework.status import (
+    HTTP_200_OK,
+)
+from rest_framework.test import APIClient
+
+from core import factories
+
+pytestmark = pytest.mark.django_db
+
+
+@override_settings(SENTRY_DSN="https://sentry.test/123")
+def test_api_config_anonymous():
+    """Anonymous users should be allowed to get the configuration."""
+    client = APIClient()
+    response = client.get("/api/v1.0/config/")
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "LANGUAGES": [["en-us", "English"], ["fr-fr", "French"], ["de-de", "German"]],
+        "LANGUAGE_CODE": "en-us",
+        "SENTRY_DSN": "https://sentry.test/123",
+        "ENVIRONMENT": "test",
+    }
+
+
+@override_settings(SENTRY_DSN="https://sentry.test/123")
+def test_api_config_authenticated():
+    """Authenticated users should be allowed to get the configuration."""
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    response = client.get("/api/v1.0/config/")
+    assert response.status_code == HTTP_200_OK
+    assert response.json() == {
+        "LANGUAGES": [["en-us", "English"], ["fr-fr", "French"], ["de-de", "German"]],
+        "LANGUAGE_CODE": "en-us",
+        "SENTRY_DSN": "https://sentry.test/123",
+        "ENVIRONMENT": "test",
+    }