feat(steady): 完善稳态数据视图功能

- 更新纵坐标刻度算法，优化小数趋势图范围显示
- 添加稳态趋势图全屏模式和共享工具组件
- 实现多图联动的鼠标悬停竖线同步功能
- 调整主线线宽分档策略，降低最大线宽限制
- 重构稳态趋势工具栏，优化谐波次数选择逻辑
- 添加周时间周期搜索支持和自定义时间范围选择
- 完善稳态数据表格和指示器浮动面板功能
- 优化稳态趋势图性能，添加LTB采样和动画控制
- 修复数据表格打开前的趋势数据验证问题
- 统一时间轴标签格式化和网格对齐处理

frontend/src/views/steady/steadyDataView/contracts/check-missing-data-contract.mjs

@@ -0,0 +1,57 @@
+/* eslint-env node */
+import fs from 'node:fs'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url'
+
+const currentDir = path.dirname(fileURLToPath(import.meta.url))
+const chartPanelFile = path.resolve(currentDir, '../components/SteadyTrendChartPanel.vue')
+const trendOptionsFile = path.resolve(currentDir, '../utils/trendOptions.ts')
+
+const chartPanelSource = fs.readFileSync(chartPanelFile, 'utf8')
+const trendOptionsSource = fs.readFileSync(trendOptionsFile, 'utf8')
+
+const checks = [
+    ['chart panel defines missing data tool action', /'missing-data'/, chartPanelSource],
+    ['chart panel labels missing data action', /action:\s*'missing-data'[\s\S]*label:/, chartPanelSource],
+    [
+        'chart panel defaults missing data enabled for every query',
+        /const\s+missingDataEnabled\s*=\s*ref\(true\)/,
+        chartPanelSource
+    ],
+    [
+        'chart panel marks missing data action active only when enabled',
+        /action\s*===\s*'missing-data'[\s\S]*return\s+missingDataEnabled\.value/,
+        chartPanelSource
+    ],
+    [
+        'chart panel passes missing data state into chart options',
+        /buildSteadyTrendChartGroups\([^)]*trendXZoomRange\.value[\s\S]*showMissingData:\s*missingDataEnabled\.value/,
+        chartPanelSource
+    ],
+    ['chart options accept missing data option', /showMissingData\?:\s*boolean/, trendOptionsSource],
+    [
+        'chart options only fills missing data when enabled',
+        /chartOptions\.showMissingData\s*===\s*true\s*\?\s*fillSteadyTrendMissingPoints\(/,
+        trendOptionsSource
+    ],
+    [
+        'missing data filler inserts null values',
+        /fillSteadyTrendMissingPoints[\s\S]*value:[\s\S]*:\s*null/,
+        trendOptionsSource
+    ],
+    [
+        'missing data filler infers interval from existing time gaps',
+        /resolveSteadyTrendPointIntervalMs[\s\S]*gaps[\s\S]*Math\.min/,
+        trendOptionsSource
+    ]
+]
+
+const failed = checks.filter(([, pattern, source]) => !pattern.test(source)).map(([message]) => message)
+
+if (failed.length) {
+    console.error('steadyDataView missing data contract failed:')
+    failed.forEach(message => console.error(`- ${message}`))
+    process.exit(1)
+}
+
+console.log('steadyDataView missing data contract passed')