lint: ruff format + one auto-fix so the push self-test is green again

`scripts/lint.sh --fix` from the pinned lint devshell: 90 Python files
reformatted (ruff format, mechanical) and one C420 (dict comprehension →
dict.fromkeys) in tests/unit/test_f211_sso_skip.py. The push self-test had
been failing at the lint stage since build 1313 (2026-08-31) on exactly
these files; nothing else changed.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FqkQq3CDmFWcQ7u1LzoyRz

tests/ghost/custom/test_content_api.py

@@ -35,10 +35,10 @@ def test_content_api_settings_endpoint(live_app):
     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}"
+        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}"
+        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}"
+        )