feat: 实现供水运营专题大屏BI可视化

- 新增OperationDashboard.vue全屏大屏组件
- 添加6个核心KPI指标卡片: 进水总量/出水总量/产销差率/营收额/平均水质/报警次数
- 实现6个ECharts图表: 供水趋势/水质分布/报警统计/管网空间/设备状态/营收分析
- 创建静态HTML版本operation-dashboard.html，使用CDN加载Vue3/ECharts/Element Plus
- 更新路由配置，添加/operation路径支持
- 修复nextTick导入问题，优化build脚本

🚧 开发者: bot_dev1
📝 任务: #38 [BI] 运营仪表盘 + 供水专题大屏

frontend/node_modules/@cesium/engine/Source/Scene/AlphaMode.js

@@ -0,0 +1,37 @@
+// @ts-check
+
+/**
+ * The alpha rendering mode of the material.
+ *
+ * @enum {string}
+ * @private
+ */
+const AlphaMode = {
+  /**
+   * The alpha value is ignored and the rendered output is fully opaque.
+   *
+   * @type {string}
+   * @constant
+   */
+  OPAQUE: "OPAQUE",
+
+  /**
+   * The rendered output is either fully opaque or fully transparent depending on the alpha value and the specified alpha cutoff value.
+   *
+   * @type {string}
+   * @constant
+   */
+  MASK: "MASK",
+
+  /**
+   * The rendered output is composited onto the destination with alpha blending.
+   *
+   * @type {string}
+   * @constant
+   */
+  BLEND: "BLEND",
+};
+
+Object.freeze(AlphaMode);
+
+export default AlphaMode;