feat(admin): 管理端 UI/UX 深度优化——错误/加载/空状态、表单快捷键、移动端适配与无障碍

apps/admin/src/pages/Dashboard/DashboardLazyCards.tsx

@@ -49,13 +49,15 @@ export const ClassroomHeatmapCard: React.FC<{
       minHeight={isMobile ? 340 : 440}
       style={{ marginBottom: 24 }}
     >
-      {data.length > 0 ? (
+      {data.some((r) => Number(r.occupancy) > 0) ? (
         <ReactECharts
           option={buildClassroomHeatmapOption(data)}
           style={{ width: '100%', height: isMobile ? 300 : 400 }}
         />
       ) : (
-        <div style={{ textAlign: 'center', padding: 40, color: '#999' }}>暂无教室数据</div>
+        <div style={{ textAlign: 'center', padding: 40, color: '#999' }}>
+          暂无教室占用数据
+        </div>
       )}
     </LazySection>
   );