update orders table

backend/migrations/2025_11_11_083522_create_orders_table.php

@@ -40,7 +40,7 @@ return new class extends Migration
             $table->text('province')->nullable()->default(null)->comment('省');
             $table->text('country')->nullable()->default(null)->comment('国家');
             $table->jsonb('raw')->nullable()->default(null)->comment('远程原始数据');
-            $table->jsonb('ext')->nullable()->default()->comment('扩展字段');
+            $table->jsonb('ext')->nullable()->default(null)->comment('扩展字段');
             $table->timestampsTz();
             // 索引
             $table->index('company_id');