feat:법인카드 결제 항목(items) JSON 컬럼 추가 마이그레이션

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

database/migrations/2026_02_20_add_items_to_corporate_card_prepayments.php

@@ -0,0 +1,22 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('corporate_card_prepayments', function (Blueprint $table) {
+            $table->json('items')->nullable()->comment('결제 항목 [{date, amount, description}]')->after('memo');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('corporate_card_prepayments', function (Blueprint $table) {
+            $table->dropColumn('items');
+        });
+    }
+};