test(settings): include preset fields in /ui-preferences pin assertion
Follow-up to the temperature & fan-speed presets feature — the
TestUiPreferencesEndpoint.test_returns_expected_field_set test pins
the exact set of fields the endpoint exposes (so adding a sensitive
field by accident fails the assert). The 4 preset fields were added
to _UI_PREFERENCE_FIELDS without updating the pin, breaking the full
backend test run.