仪表盘重做：ECharts 曲线、常驻遥测、路由行直达详情

采集从仪表盘组件挪进模块级单例（web/telemetry.ts），流量曲线和每路
吞吐的历史跨页面留存——跟着组件走的话切一次页面就清零一次。每路吞吐
从 /connections 快照按连接逐条求差再按 inboundName 聚合：先求和再求差
会在连接关闭时算出负数。

图表换 ECharts（按需注册）：手写 SVG 折线做不出平滑曲线和时间轴，
颜色在运行时从 CSS 变量取，跟随主题切换重取。

路由列表每行带走势、速率和可选的公网 IP 检测，点击跳路由页并选中
那一路（外壳传 focus 给 RouterPage 消费）。

shared/telemetry.test.ts

@@ -0,0 +1,100 @@
+import { describe, expect, test } from 'bun:test'
+import {
+  lastRate,
+  pushWindow,
+  routeDeltas,
+  windowBytes,
+  type ConnTotals,
+  type RouteSample,
+} from './telemetry.ts'
+import type { ConnectionItem } from './connections.ts'
+
+function conn(id: string, inbound: string, upload: number, download: number): ConnectionItem {
+  return {
+    id,
+    upload,
+    download,
+    start: '2026-08-11T00:00:00+08:00',
+    chains: ['DIRECT'],
+    rule: 'Match',
+    rulePayload: '',
+    metadata: {
+      host: 'example.com',
+      destinationIP: '1.2.3.4',
+      destinationPort: '443',
+      inboundName: inbound,
+      inboundPort: '7890',
+    },
+  }
+}
+
+describe('pushWindow', () => {
+  test('把窗口外的老点挤掉，保留窗口内的', () => {
+    const list = [{ t: 0 }, { t: 5_000 }, { t: 9_000 }]
+    const next = pushWindow(list, { t: 12_000 }, 5_000)
+    expect(next.map((p) => p.t)).toEqual([9_000, 12_000])
+  })
+
+  test('全部过期时只剩新点', () => {
+    const next = pushWindow([{ t: 0 }], { t: 60_000 }, 5_000)
+    expect(next.map((p) => p.t)).toEqual([60_000])
+  })
+})
+
+describe('routeDeltas', () => {
+  test('已有连接算差值，并按入站聚合', () => {
+    const prev: ConnTotals = new Map([
+      ['a', { up: 100, down: 200 }],
+      ['b', { up: 10, down: 20 }],
+    ])
+    const { deltas } = routeDeltas(prev, [
+      conn('a', 'lan-a', 150, 260),
+      conn('b', 'lan-a', 30, 21),
+    ])
+    expect(deltas['lan-a']).toEqual({ up: 70, down: 61 })
+  })
+
+  test('新连接把累计全部记入本次间隔', () => {
+    const { deltas } = routeDeltas(new Map(), [conn('a', 'lan-a', 500, 700)])
+    expect(deltas['lan-a']).toEqual({ up: 500, down: 700 })
+  })
+
+  test('累计变小（内核重启）按全新连接处理，不出负数', () => {
+    const prev: ConnTotals = new Map([['a', { up: 900, down: 900 }]])
+    const { deltas } = routeDeltas(prev, [conn('a', 'lan-a', 50, 60)])
+    expect(deltas['lan-a']).toEqual({ up: 50, down: 60 })
+  })
+
+  test('消失的连接不再出现在 next 里', () => {
+    const prev: ConnTotals = new Map([['gone', { up: 1, down: 1 }]])
+    const { next } = routeDeltas(prev, [conn('a', 'lan-a', 5, 5)])
+    expect(next.has('gone')).toBe(false)
+    expect(next.get('a')).toEqual({ up: 5, down: 5 })
+  })
+
+  test('没有名字的入站退回端口做键', () => {
+    const item = conn('a', '', 5, 5)
+    const { deltas } = routeDeltas(new Map(), [item])
+    expect(Object.keys(deltas)).toEqual(['7890'])
+  })
+})
+
+describe('windowBytes / lastRate', () => {
+  const samples: RouteSample[] = [
+    { t: 0, ms: 3_000, up: 100, down: 100 },
+    { t: 3_000, ms: 3_000, up: 300, down: 300 },
+    { t: 6_000, ms: 2_000, up: 400, down: 600 },
+  ]
+
+  test('windowBytes 只算窗口内的样本', () => {
+    expect(windowBytes(samples, 3_000)).toBe(300 + 300 + 400 + 600)
+  })
+
+  test('lastRate 按实际间隔换算成每秒', () => {
+    expect(lastRate(samples)).toEqual({ up: 200, down: 300 })
+  })
+
+  test('lastRate 没有样本时是 null', () => {
+    expect(lastRate([])).toBeNull()
+  })
+})