test(acl,verify): cancellation reaches Geannuleerd live (refs #106)

Adds an ACL↔OpenZaak integration test asserting SetZaakToCancellationStatusAsync
records the Geannuleerd status + a resultaat against real OpenZaak, and extends
the domain verify script to confirm a timed-out registration's zaak is cancelled
to Geannuleerd end-to-end.

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

services/acl/Acl.IntegrationTests/OpenZaakFixture.cs

@@ -114,6 +114,19 @@ public sealed class OpenZaakFixture : IDisposable
         return fallback ?? throw new InvalidOperationException($"No statustypen for zaaktype {zaaktypeUrl}");
     }
 
+    /// <summary>Resolve a statustype by its omschrijving (e.g. the S-10c "Geannuleerd" cancellation status).</summary>
+    public async Task<Uri> FindStatustypeByOmschrijvingAsync(Uri zaaktypeUrl, string omschrijving, CancellationToken ct = default)
+    {
+        var query = new Uri(BaseUrl,
+            "/catalogi/api/v1/statustypen?status=alles&zaaktype=" + Uri.EscapeDataString(zaaktypeUrl.ToString()));
+        var page = await GetJsonAsync(query, ct);
+        foreach (var st in page.GetProperty("results").EnumerateArray())
+            if (st.TryGetProperty("omschrijving", out var o) && o.GetString() == omschrijving)
+                return new Uri(st.GetProperty("url").GetString()!);
+
+        throw new InvalidOperationException($"No '{omschrijving}' statustype for zaaktype {zaaktypeUrl}");
+    }
+
     // A ZGW (vng-api-common) HS256 JWT, mirroring the seed's client. Minted here
     // rather than reusing Acl.Infrastructure's internal minter to keep that internal.
     private string MintToken()