fix: stabilize flaky E2E booking sheet tests by waiting for button visibility (#28631)

Both booking-sheet-keyboard.e2e.ts and bookings-list.e2e.ts intermittently
timeout in CI when clicking the booking item button before the DOM has
finished rendering. Adding explicit waitFor({ state: 'visible' }) on the
role=button element after the parent booking item is visible ensures the
click target is fully ready.

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/web/playwright/booking-sheet-keyboard.e2e.ts

@@ -100,7 +100,9 @@ async function setupBookingsAndOpenSheet({
 
   const firstBookingItem = page.locator(`[data-booking-uid="${fixtures[0].uid}"]`);
   await expect(firstBookingItem).toBeVisible();
-  await firstBookingItem.locator('[role="button"]').first().click();
+  const firstButton = firstBookingItem.locator('[role="button"]').first();
+  await firstButton.waitFor({ state: "visible" });
+  await firstButton.click();
 
   const sheet = page.locator('[role="dialog"]');
   await expect(sheet).toBeVisible();

apps/web/playwright/bookings-list.e2e.ts

@@ -798,8 +798,9 @@ test.describe("Bookings", () => {
 
       const bookingItem = page.locator(`[data-booking-uid="${bookingFixture.uid}"]`);
       await expect(bookingItem).toBeVisible();
-
-      await bookingItem.locator('[role="button"]').first().click();
+      const bookingButton = bookingItem.locator('[role="button"]').first();
+      await bookingButton.waitFor({ state: "visible" });
+      await bookingButton.click();
 
       await expect(page).toHaveURL(new RegExp(`[?&]uid=${bookingFixture.uid}(&|$)`));
     } finally {