settingForYamlKey function
The SharedSetting that owns the yaml top-level key, or null when no
shared setting covers it (the key must then be in fileOnlyConfigKeys
or it is unclassified — the completeness gate fails).
Implementation
SharedSetting? settingForYamlKey(String key) {
for (final entry in sharedSettingMetadata.entries) {
if (entry.value.yamlKeys.contains(key)) return entry.key;
}
return null;
}