test(e2e): click the always-present vaccination add button

The capture helper branched on an instant isVisible() read to pick between the
header add and the empty-state add. Right after a navigation that read races the
client render and loses, so it fell through to the empty-state button, which is
gone once a record exists, and the click timed out. The header add renders in
both states; clicking it directly lets click() auto-wait for hydration.

e2e/vaccinations.spec.ts

@@ -84,14 +84,11 @@ async function captureDose(
     booster: "confirm" | "decline" | "none";
   },
 ): Promise<void> {
-  const add = page.locator('[data-slot="vaccination-add"]').first();
-  const addEmpty = page.locator('[data-slot="vaccination-add-empty"]').first();
-  // The list uses a header Add; the empty state uses its own.
-  if (await add.isVisible().catch(() => false)) {
-    await add.click();
-  } else {
-    await addEmpty.click();
-  }
+  // The header Add renders whether or not the list is empty, so clicking it
+  // works in both states. click() auto-waits for the button to be actionable,
+  // which avoids racing an instant visibility read against the client render
+  // (an empty-state-only branch times out once a record already exists).
+  await page.locator('[data-slot="vaccination-add"]').first().click();
 
   await expect(page.locator('[data-slot="vaccination-form"]')).toBeVisible();