fix(web-app-shopware): assert the login form on Shopware, not on the logout page

The native admin spec clicked in-app logout and then waited 60s for a password field on whatever page it had landed on. That page is never Shopware: with web-svc-logout attached, the flow ends on logout.<domain>, the universal-logout status page, which is terminal by design (README: "Front Channel Logout URL ... status page with live feedback").

Evidence from job 95883075100: the error-context snapshot shows heading "Logging out" plus paragraph "You are logging out from following apps" and a list - the web-svc-logout UI, not Keycloak's end-session page, which carries a Logout button instead (that one was already handled by a30d67a63). The openresty access log confirms the chain at 03:38:58: POST /realms/.../logout/logout-confirm 200, then GET logout.infinito.example/?sid=...&iss=... 200, 2555 bytes.

Returning to ${appBaseUrl}/admin before the expectation puts the claim where it can be true or false. This is the same move c7e5b0a27 made for web-app-funkwhale, and the shared persona flow has always done it via assertUnauthenticatedLanding (personas/utils/landing.js). The assertion itself is untouched, so the test gets stricter, not more lenient: a session that survived logout now fails here instead of at a spot that said nothing about it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

roles/web-app-shopware/files/playwright/test-admin-native.js

@@ -77,6 +77,7 @@ test("administrator: admin login → catalogue → in-app logout", async ({ page
   await logout.click();
   await page.waitForLoadState("domcontentloaded", { timeout: resolveTimeout(30_000) }).catch(() => {});
   await confirmKeycloakLogoutIfPrompted(page);
+  await gotoOnion(page, `${appBaseUrl}/admin`, { waitUntil: "domcontentloaded" });
 
   await expect(
     page.locator("input[type='password']:visible").first(),