Add e2e coverage for deferred payment and admin lookup.

Manual Swish flow means users often pay later; admins match payments via
order ID or regnr under Att göra.

- User flow: create order, leave payment, pay from orders page
- Admin: find order via partial ID, full ID, and plate search
- Assert unpaid orders appear under Väntar, not Att göra
- Use unique plates per run to avoid collisions with seed data

frontend/e2e/deferred-payment-admin.spec.ts

@@ -0,0 +1,144 @@
+import { test, expect } from '@playwright/test'
+
+test.describe.configure({ mode: 'serial' })
+
+function uniquePlate(prefix: string): string {
+  const digits = String((Date.now() % 90) + 10)
+  return `${prefix}${digits}E`
+}
+
+test.describe('Deferred payment and admin lookup', () => {
+  const plate = uniquePlate('LAT')
+  const letterText = 'E2E-test: betalar senare från orderhistoriken.'
+
+  let orderId = ''
+  let shortOrderId = ''
+
+  async function loginAsTestUser(page: import('@playwright/test').Page) {
+    await page.goto('/logga-in')
+    await page.getByLabel('E-postadress').fill('test@bilhalsning.se')
+    await page.getByLabel('Lösenord').fill('test1234')
+    await page.getByRole('button', { name: 'Logga in' }).click()
+    await page.waitForURL('/')
+  }
+
+  async function loginAsAdmin(page: import('@playwright/test').Page) {
+    await page.goto('/logga-in')
+    await page.getByLabel('E-postadress').fill('admin@bilhalsning.se')
+    await page.getByLabel('Lösenord').fill('test1234')
+    await page.getByRole('button', { name: 'Logga in' }).click()
+    await page.waitForURL('/')
+  }
+
+  async function completeSwishPayment(page: import('@playwright/test').Page) {
+    await page.getByRole('button', { name: 'Jag har betalat' }).click()
+    await page.getByRole('button', { name: 'Ja, jag har betalat' }).click()
+  }
+
+  test('user creates order, leaves payment, and pays later from orders', async ({
+    page,
+  }) => {
+    await loginAsTestUser(page)
+
+    await page.goto(`/compose?plate=${plate}`)
+    await page.getByLabel('Ditt meddelande').fill(letterText)
+    await page.getByRole('button', { name: 'Fortsätt till betalning' }).click()
+
+    await page.waitForURL(/\/betalning\/[a-f0-9-]+/i)
+    const match = page.url().match(/\/betalning\/([a-f0-9-]+)/i)
+    expect(match).not.toBeNull()
+    orderId = match![1]
+    shortOrderId = orderId.slice(0, 8)
+
+    await expect(page.locator('.payment__order-id')).toHaveText(orderId)
+
+    await page.goto('/')
+    await page.getByRole('link', { name: 'Mina beställningar' }).click()
+    await expect(page).toHaveURL('/orders')
+
+    const orderCard = page.locator('.orders__card', { hasText: orderId })
+    await expect(orderCard.getByText(plate)).toBeVisible()
+    await expect(orderCard.locator('.badge')).toHaveText('Väntar på betalning')
+    await expect(orderCard.getByRole('link', { name: 'Betala nu' })).toBeVisible()
+
+    await orderCard.getByRole('link', { name: 'Betala nu' }).click()
+    await expect(page).toHaveURL(new RegExp(`/betalning/${orderId}`))
+    await completeSwishPayment(page)
+
+    await expect(page).toHaveURL('/orders')
+    await expect(orderCard.locator('.badge')).toHaveText('Hanteras')
+    await expect(orderCard.getByRole('link', { name: 'Betala nu' })).not.toBeVisible()
+  })
+
+  test('admin finds paid order under Att göra when searching partial order id', async ({
+    page,
+  }) => {
+    await loginAsAdmin(page)
+    await page.goto('/admin')
+
+    await page.getByRole('button', { name: /Att göra/ }).click()
+    await page.locator('#admin-order-search').fill(shortOrderId)
+
+    const row = page.locator('.admin__row', { hasText: shortOrderId })
+    await expect(row).toBeVisible()
+    await expect(row.locator('.admin__order-id')).toHaveText(shortOrderId)
+    await expect(row.locator('.admin__plate')).toHaveText(plate)
+    await expect(row).toHaveClass(/admin__row--todo/)
+  })
+
+  test('admin finds paid order when searching full order id', async ({ page }) => {
+    await loginAsAdmin(page)
+    await page.goto('/admin')
+
+    await page.getByRole('button', { name: /Att göra/ }).click()
+    await page.locator('#admin-order-search').fill(orderId)
+
+    const row = page.locator('.admin__row', { hasText: shortOrderId })
+    await expect(row).toBeVisible()
+    await expect(row.locator('.admin__order-id')).toHaveText(shortOrderId)
+    await expect(row.locator('.admin__plate')).toHaveText(plate)
+  })
+
+  test('admin finds paid order when searching registration number', async ({
+    page,
+  }) => {
+    await loginAsAdmin(page)
+    await page.goto('/admin')
+
+    await page.getByRole('button', { name: /Att göra/ }).click()
+    await page.locator('#admin-order-search').fill(plate)
+
+    const row = page.locator('.admin__row', { hasText: shortOrderId })
+    await expect(row).toBeVisible()
+    await expect(row.locator('.admin__plate')).toHaveText(plate)
+  })
+
+  test('admin does not show unpaid order under Att göra before payment', async ({
+    page,
+  }) => {
+    await loginAsTestUser(page)
+
+    const unpaidPlate = uniquePlate('UNP')
+    await page.goto(`/compose?plate=${unpaidPlate}`)
+    await page.getByLabel('Ditt meddelande').fill('E2E-test: ska ligga under Väntar.')
+    await page.getByRole('button', { name: 'Fortsätt till betalning' }).click()
+    await page.waitForURL(/\/betalning\/([a-f0-9-]+)/i)
+    const unpaidMatch = page.url().match(/\/betalning\/([a-f0-9-]+)/i)
+    const unpaidOrderId = unpaidMatch![1]
+    const unpaidShortId = unpaidOrderId.slice(0, 8)
+    await page.goto('/orders')
+
+    await page.evaluate(() => localStorage.clear())
+    await loginAsAdmin(page)
+    await page.goto('/admin')
+    await page.getByRole('button', { name: /Att göra/ }).click()
+
+    const unpaidRow = page.locator('.admin__row', { hasText: unpaidShortId })
+    await expect(unpaidRow).not.toBeVisible()
+
+    await page.getByRole('button', { name: /Väntar/ }).click()
+    await page.locator('#admin-order-search').fill(unpaidPlate)
+    await expect(unpaidRow).toBeVisible()
+    await expect(unpaidRow.locator('.admin__plate')).toHaveText(unpaidPlate)
+  })
+})