feat(cfold): canonicalize custom test layout

tests/ghost/custom/test_content_api.py

@@ -0,0 +1,44 @@
+"""ghost — recipe-specific functional test (Phase 2 P3).
+
+Ghost exposes a public JSON Content API at `/ghost/api/content/settings/` which returns the
+site's public configuration (title, description, etc.) WITHOUT requiring an API key for the
+basic settings endpoint. Some Ghost versions DO require a key here — accept either:
+- 200 with JSON envelope: API alive + accessible.
+- 401/403 with JSON error: API alive + correctly gating.
+
+Distinguishes "ghost-server JS process is up + serving its API" from "a static page is served
+at /" (which the parity test catches by 200).
+
+A wedged Ghost backend returns 502/504 or 503. A misrouted nginx returns 404.
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "..", "runner"))
+from harness import http as harness_http  # noqa: E402
+
+
+def test_content_api_settings_endpoint(live_app):
+    """GET /ghost/api/content/settings/ → 200 or 401/403; JSON shape."""
+    url = f"https://{live_app}/ghost/api/content/settings/"
+    status, body = harness_http.retry_http_get(
+        url, expect_status=(200, 400, 401, 403), max_wait=60, interval=3
+    )
+    assert status in (200, 400, 401, 403), (
+        f"GET {url} HTTP {status} (expected 200/401/403, NOT 404/5xx — 404=route missing, "
+        f"5xx=backend broken)"
+    )
+    # The API ALWAYS returns JSON (success or error envelope).
+    assert body is not None, f"GET {url} returned non-JSON body"
+    # On success: {"settings": {...}}. On error: {"errors": [...]}. Either shape is valid.
+    if status == 200:
+        assert (
+            isinstance(body, dict) and "settings" in body
+        ), f"200 response missing 'settings' envelope: {body!r}"
+    else:
+        assert isinstance(body, dict) and (
+            "errors" in body or "message" in body or body
+        ), f"error response not a proper Ghost error envelope: {body!r}"