localizationMiddleware function
Creates middleware that runs the LocaleManager before downstream handlers.
The resolved locale is stored under kRequestLocaleAttribute so helpers
such as trans can pick it up.
Implementation
Middleware localizationMiddleware(LocaleManager manager) {
return (EngineContext ctx, Next next) async {
final context = LocaleResolutionContext.fromContext(ctx);
final locale = manager.resolve(context);
ctx.set(kRequestLocaleAttribute, locale);
return await next();
};
}