fix(e2e): await the decide POST before leaving the werkbak page (refs #13)

The happy path clicked Goedkeuren and immediately navigated to the openbaar register, which

cancelled the in-flight POST /behandel/registrations/{id}/decide (nginx 499) — the decision

never reached the domain, so the registration stayed INGEDIEND and the final INGESCHREVEN

assertion failed. Wait for the decide response (204) before navigating away.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/e2e/registration.spec.ts

@@ -66,7 +66,16 @@ test('DigiD submit → public INGEDIEND → behandelaar goedkeurt → public ING
     }, { timeout: 30_000, intervals: [1_000, 2_000, 3_000, 5_000] })
     .toBeGreaterThan(0);
 
+  // Click and wait for the decide POST to finish (204) BEFORE leaving the page. `click()` only
+  // dispatches the request; navigating away immediately cancels it in flight (nginx logs a 499) and
+  // the decision never reaches the domain — so the registration would stay INGEDIEND.
+  const decided = page.waitForResponse(
+    (r) =>
+      r.url().includes(`/behandel/registrations/${reference}/decide`) &&
+      r.request().method() === 'POST',
+  );
   await goedkeuren.click();
+  expect((await decided).status()).toBe(204);
 
   // The approval flows back to the projection; back on the openbaar register *our* row (matched by
   // its reference) now shows INGESCHREVEN.