fix user table

backend/migrations/2025_11_10_021005_create_users_table.php

@@ -12,7 +12,7 @@ return new class extends Migration
     public function up(): void
     {
         Schema::create('users', function (Blueprint $table) {
-            $table->bigIncrements('id');
+            $table->bigIncrements('id')->comment('主键');
             $table->string('username', 100)->unique()->comment('用户名');
             $table->string('password')->comment('密码');
             $table->string('email', 100)->unique()->comment('邮箱');