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/Source/Widgets/InfoBox/InfoBox.css

@@ -0,0 +1,103 @@
+.cesium-infoBox {
+  display: block;
+  position: absolute;
+  top: 50px;
+  right: 0;
+  width: 40%;
+  max-width: 480px;
+  background: rgba(38, 38, 38, 0.95);
+  color: #edffff;
+  border: 1px solid #444;
+  border-right: none;
+  border-top-left-radius: 7px;
+  border-bottom-left-radius: 7px;
+  box-shadow: 0 0 10px 1px #000;
+  transform: translate(100%, 0);
+  visibility: hidden;
+  opacity: 0;
+  transition:
+    visibility 0s 0.2s,
+    opacity 0.2s ease-in,
+    transform 0.2s ease-in;
+}
+
+.cesium-infoBox-visible {
+  transform: translate(0, 0);
+  visibility: visible;
+  opacity: 1;
+  transition:
+    opacity 0.2s ease-out,
+    transform 0.2s ease-out;
+}
+
+.cesium-infoBox-title {
+  display: block;
+  height: 20px;
+  padding: 5px 30px 5px 25px;
+  background: rgba(84, 84, 84, 1);
+  border-top-left-radius: 7px;
+  text-align: center;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+  overflow: hidden;
+  box-sizing: content-box;
+}
+
+.cesium-infoBox-bodyless .cesium-infoBox-title {
+  border-bottom-left-radius: 7px;
+}
+
+button.cesium-infoBox-camera {
+  display: block;
+  position: absolute;
+  top: 4px;
+  left: 4px;
+  width: 22px;
+  height: 22px;
+  background: transparent;
+  border-color: transparent;
+  border-radius: 3px;
+  padding: 0 5px;
+  margin: 0;
+}
+
+button.cesium-infoBox-close {
+  display: block;
+  position: absolute;
+  top: 5px;
+  right: 5px;
+  height: 20px;
+  background: transparent;
+  border: none;
+  border-radius: 2px;
+  font-weight: bold;
+  font-size: 16px;
+  padding: 0 5px;
+  margin: 0;
+  color: #edffff;
+}
+
+button.cesium-infoBox-close:focus {
+  background: rgba(238, 136, 0, 0.44);
+  outline: none;
+}
+
+button.cesium-infoBox-close:hover {
+  background: #888;
+  color: #000;
+}
+
+button.cesium-infoBox-close:active {
+  background: #a00;
+  color: #000;
+}
+
+.cesium-infoBox-bodyless .cesium-infoBox-iframe {
+  display: none;
+}
+
+.cesium-infoBox-iframe {
+  border: none;
+  width: 100%; /* Fallback */
+  width: calc(100% - 2px);
+}