test(domain): timeout worker no-ops on an already-resolved registration (refs #102)

RED: if the citizen withdrew while parked at WachtOpDocumenten, the RegistratieVerlopen
job finds a terminal (INGETROKKEN) aggregate; the worker must no-op and let the job
complete, not throw into a redelivery loop.

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

services/domain/Big.Tests/ExpireRegistrationWorkerTests.cs

@@ -48,6 +48,25 @@ public class ExpireRegistrationWorkerTests
         Assert.Equal(RegistrationStatus.Verlopen, (await store.GetAsync(registration.Id))!.Status);
     }
 
+    [Fact]
+    public async Task An_already_resolved_registration_is_left_alone_and_the_job_completes()
+    {
+        // Race with S-11: the citizen withdrew while parked at WachtOpDocumenten, so the aggregate is
+        // already terminal (INGETROKKEN) when the timer's job arrives. Expiring it would violate the
+        // aggregate's invariant; the worker must instead no-op (and let the job complete), not throw
+        // into a redelivery loop.
+        var store = new FakeRegistrationStore();
+        var registration = Submitted();
+        registration.Withdraw();
+        store.Seed(registration);
+
+        await new ExpireRegistrationWorker(store).HandleAsync(
+            new RegistratieVerlopenJob("job-7", registration.Id));
+
+        Assert.Equal(0, store.SaveCount);
+        Assert.Equal(RegistrationStatus.Ingetrokken, (await store.GetAsync(registration.Id))!.Status);
+    }
+
     [Fact]
     public async Task An_unknown_registration_throws_so_the_job_is_redelivered()
     {