refactor：拆分 API 路由与请求校验，统一 final 类和代码风格

app/Http/Middleware/NegotiateLotteryLocale.php

@@ -2,9 +2,9 @@
 
 namespace App\Http\Middleware;
 
-use App\Support\LotteryLocale;
 use Closure;
 use Illuminate\Http\Request;
+use App\Support\LotteryLocale;
 use Symfony\Component\HttpFoundation\Response;
 
 /**
@@ -20,7 +20,7 @@ use Symfony\Component\HttpFoundation\Response;
  *
  * 【与异常 JSON】{@see LotteryLocale} 与 middleware 同源，在未命中路由、`lottery_locale` 未写入时仍可从 Header 推导。
  */
-class NegotiateLotteryLocale
+final class NegotiateLotteryLocale
 {
     public function handle(Request $request, Closure $next): Response
     {