Test the two gestures the rework is actually about

The browser suite checked what the app renders but nothing about authoring,
which is the part that changed. It now registers a fresh account and walks
the wizard, including the case where a partner added mid-wizard has to appear
by name without navigating away first, and it drags a range on the calendar,
deletes the period, and reloads to confirm the days really went. Both are
regressions that were found by hand within the last day and would have been
found here instead.

Doing this surfaced that the age-four spec had been asserting on figures that
moved inside a collapsed section, so it had stopped checking anything. The
stale note about the retired tips page went too.

frontend/e2e/tests/age4.spec.ts

@@ -43,6 +43,13 @@ test('per-parent expiring/savable figures respect the 48/96 age-4 cap, and the D
   await page.goto('/')
   await expect(page.getByTestId('dashboard')).toBeVisible()
 
+  // The per-parent/combined metrics live inside the collapsed "Fler
+  // detaljer" <details> disclosure (Dashboard.tsx's
+  // `dashboard-more-details`) — open it before asserting anything inside,
+  // otherwise every element in there is genuinely hidden (native <details>
+  // collapse, not just scrolled out of view).
+  await page.locator('[data-testid="dashboard-more-details"] summary').click()
+
   for (const projection of overview.parent_projections) {
     const metric = page.getByTestId(`metric-expiring-parent-${projection.personal_data_uuid}`)
     await expect(metric).toBeVisible()