applyEnsembleTestTheme function
Applies raw via EnsembleThemeManager when that theme is registered.
Returns the resolved theme name when applied, otherwise null.
Implementation
String? applyEnsembleTestTheme(String? raw) {
final manager = EnsembleThemeManager();
final name = resolveEnsembleThemeName(
raw,
registeredNames: manager.getThemeNames(),
);
if (name == null) return null;
if (manager.currentThemeName == name) return name;
manager.setTheme(name);
return name;
}