feat: 添加数据库索引优化查询性能

refactor(前端): 使用useMemo和useCallback优化性能
perf(后端): 优化统计查询性能
style: 统一前端样式定义
build: 添加创建索引脚本

backend/models/Consumable.js

@@ -57,7 +57,12 @@ const Consumable = sequelize.define('Consumable', {
   }
 }, {
   tableName: 'consumables',
-  timestamps: true
+  timestamps: true,
+  indexes: [
+    { fields: ['category'] },
+    { fields: ['status'] },
+    { fields: ['category', 'status'] }
+  ]
 });
 
 module.exports = Consumable;