ui(cupang): 박스 입수량 2열 배치 + 고정폭 + 입수량 "개" 단위

- 추가/수정 480px(좌), 입수량 규칙 900px(우)
- 제품명/제품코드/박스이름 입력 140px, 박스당 입수량 60px + "개" 접미
- 캐시 버전 e

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/templates/erp_base.html

@@ -4,8 +4,8 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
     <title>{{ page_title or "ERP" }} — DBX Corporation</title>
-    <link rel="stylesheet" href="/static/erp.css?v=20260530d" />
-    <link rel="stylesheet" href="/static/erp-shell.css?v=20260530d" />
+    <link rel="stylesheet" href="/static/erp.css?v=20260530e" />
+    <link rel="stylesheet" href="/static/erp-shell.css?v=20260530e" />
     <link rel="stylesheet" href="/static/erp-attach-viewer.css" />
     {% block head_extra %}{% endblock %}
   </head>