增加板块内置顶，与全局置顶分离：首页仅抬升全局置顶，板块列表优先全局再板块。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/pages/admin/AdminDashboardPage.tsx

@@ -153,8 +153,9 @@ export default function AdminDashboardPage() {
                 </td>
                 <td className="space-x-1">
                   {p.featured ? <Badge variant="orange">精华</Badge> : null}
-                  {p.pinned ? <Badge variant="green">置顶</Badge> : null}
-                  {!p.featured && !p.pinned ? '—' : null}
+                  {p.pinned ? <Badge variant="green">全局置顶</Badge> : null}
+                  {p.board_pinned ? <Badge variant="green">板块置顶</Badge> : null}
+                  {!p.featured && !p.pinned && !p.board_pinned ? '—' : null}
                 </td>
                 <td>{new Date(p.created_at).toLocaleString('zh-CN')}</td>
               </tr>