fix(ui): пояснять отсутствие отдельного направления трафика

tests/e2e/traffic-details.spec.ts

@@ -1,7 +1,7 @@
 import { test, expect, type Page } from '@playwright/test'
 
 async function setup(page: Page) {
-  const control = { holdRange: '', failIface: false, series: undefined as number[] | undefined, release: () => {} }
+  const control = { holdRange: '', failIface: false, series: undefined as number[] | undefined, txSeries: undefined as number[] | undefined, release: () => {} }
   const gate = new Promise<void>(resolve => { control.release = resolve })
   const server = { id: '1', name: 'Первый сервер', site: 'TEST', country: 'RU', status: 'online', rxNow: 2, txNow: 3, rxPeak: 5, txPeak: 6, rxTotal: 100, txTotal: 200, sessions: 1, rxSeries: [1, 2], txSeries: [2, 3] }
   await page.route('**/health', route => route.fulfill({ json: { ok: true } }))
@@ -12,7 +12,7 @@ async function setup(page: Page) {
       const range = url.searchParams.get('range'), iface = url.searchParams.get('iface')
       if (control.holdRange && range === control.holdRange) await gate
       if (control.failIface && iface === 'ether2') return route.fulfill({ status: 500, json: { error: 'Интерфейс временно недоступен' } })
-      return route.fulfill({ json: { server: { ...server, rxSeries: control.series ?? server.rxSeries, txSeries: control.series ?? server.txSeries, name: `Детали ${range} ${iface}`, rxNow: range === '24h' ? 24 : 15 } } })
+      return route.fulfill({ json: { server: { ...server, rxSeries: control.series ?? server.rxSeries, txSeries: control.txSeries ?? control.series ?? server.txSeries, name: `Детали ${range} ${iface}`, rxNow: range === '24h' ? 24 : 15 } } })
     }
     const json = path === '/api/auth/config' ? { required: false }
       : path === '/api/traffic/servers' ? { servers: [server] }
@@ -85,3 +85,22 @@ test('Трафик: пустая история отличается от нул
   await expect(page.getByRole('region', { name: 'История RX/TX' })).toBeVisible()
   await expect(page.getByText('Нет исторических измерений за выбранный период', { exact: true })).toHaveCount(0)
 })
+
+
+for (const missing of ['RX', 'TX'] as const) {
+  test('Трафик: отсутствие ' + missing + ' не подменяется нулевой линией', async ({ page }) => {
+    const control = await setup(page)
+    control.series = missing === 'RX' ? [] : [2, 3]
+    control.txSeries = missing === 'TX' ? [] : [2, 3]
+    await page.getByRole('button', { name: '24ч', exact: true }).click()
+    const chart = page.getByRole('region', { name: 'История RX/TX' })
+    await expect(chart.getByRole('status')).toHaveText('Нет измерений ' + missing + ' за выбранный период')
+    await expect(chart.locator('.recharts-line-curve')).toHaveCount(1)
+    const plot = chart.locator('.recharts-wrapper')
+    await plot.scrollIntoViewIfNeeded()
+    const box = await plot.boundingBox()
+    await page.mouse.move(box!.x + box!.width - 12, box!.y + box!.height / 2)
+    await expect(chart.getByText(missing + ':', { exact: true })).toHaveCount(0)
+    await expect(chart.getByText((missing === 'RX' ? 'TX' : 'RX') + ':', { exact: true })).toBeVisible()
+  })
+}