ui(shell): 브랜드 'DBX ERP System' 통일 + 사이드바 접힘 시 아이콘 아래 메뉴명 표시

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=20260530p" />
-    <link rel="stylesheet" href="/static/erp-shell.css?v=20260530p" />
+    <link rel="stylesheet" href="/static/erp.css?v=20260530q" />
+    <link rel="stylesheet" href="/static/erp-shell.css?v=20260530q" />
     <link rel="stylesheet" href="/static/erp-attach-viewer.css" />
     {% block head_extra %}{% endblock %}
   </head>
@@ -19,7 +19,7 @@
         <div class="erp-sidebar-head">
           <a href="/" class="erp-sidebar-brand">
             <img src="/static/dbx-logo.png" alt="DBX" class="erp-sidebar-logo" />
-            <span class="erp-sidebar-system">ERP</span>
+            <span class="erp-sidebar-system">DBX ERP System</span>
           </a>
           <button type="button" class="erp-sidebar-toggle" id="erp-sidebar-toggle" aria-label="사이드바 접기">
             <svg width="14" height="14" viewBox="0 0 24 24" fill="none"