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/postcss/lib/previous-map.d.ts

@@ -0,0 +1,80 @@
+import { SourceMapConsumer } from 'source-map-js'
+
+import { ProcessOptions } from './postcss.js'
+
+declare namespace PreviousMap {
+  export { PreviousMap_ as default }
+}
+
+/**
+ * Source map information from input CSS.
+ * For example, source map after Sass compiler.
+ *
+ * This class will automatically find source map in input CSS or in file system
+ * near input file (according `from` option).
+ *
+ * ```js
+ * const root = parse(css, { from: 'a.sass.css' })
+ * root.input.map //=> PreviousMap
+ * ```
+ */
+declare class PreviousMap_ {
+  /**
+   * `sourceMappingURL` content.
+   */
+  annotation?: string
+
+  /**
+   * The CSS source identifier. Contains `Input#file` if the user
+   * set the `from` option, or `Input#id` if they did not.
+   */
+  file?: string
+
+  /**
+   * Was source map inlined by data-uri to input CSS.
+   */
+  inline: boolean
+
+  /**
+   * Path to source map file.
+   */
+  mapFile?: string
+
+  /**
+   * The directory with source map file, if source map is in separated file.
+   */
+  root?: string
+
+  /**
+   * Source map file content.
+   */
+  text?: string
+
+  /**
+   * @param css  Input CSS source.
+   * @param opts Process options.
+   */
+  constructor(css: string, opts?: ProcessOptions)
+
+  /**
+   * Create a instance of `SourceMapGenerator` class
+   * from the `source-map` library to work with source map information.
+   *
+   * It is lazy method, so it will create object only on first call
+   * and then it will use cache.
+   *
+   * @return Object with source map information.
+   */
+  consumer(): SourceMapConsumer
+
+  /**
+   * Does source map contains `sourcesContent` with input source text.
+   *
+   * @return Is `sourcesContent` present.
+   */
+  withContent(): boolean
+}
+
+declare class PreviousMap extends PreviousMap_ {}
+
+export = PreviousMap