test(bff): /beheer/catalogi/zaaktypen behind beheerder authorization (refs #130)

services/bff/Bff.Api/DownstreamClients.cs

@@ -54,6 +54,19 @@ public interface IProjectionClient
     Task<IReadOnlyList<ProjectionEntry>> GetRegisterAsync(CancellationToken ct = default);
 }
 
+/// <summary>A published zaaktype as the beheer catalogus viewer shows it (S-15a): the business
+/// <c>Identificatie</c> + human <c>Omschrijving</c>. The ZGW URL the ACL also returns is dropped — an
+/// internal reference, not shown in the portal.</summary>
+public sealed record BeheerZaaktype(string Identificatie, string Omschrijving);
+
+/// <summary>Port to the ACL for read-only catalogus queries (beheer portal, S-15a). The BFF reaches the
+/// ACL directly for this read: the catalogus isn't a domain concern, and the ACL is the only code
+/// allowed to read the ZGW Catalogi API (§8.1, ADR-0025).</summary>
+public interface IAclClient
+{
+    Task<IReadOnlyList<BeheerZaaktype>> GetZaaktypenAsync(CancellationToken ct = default);
+}
+
 /// <summary>Calls the Domain Service's <c>POST /registrations</c>.</summary>
 public sealed class DomainClient(HttpClient http) : IDomainClient
 {
@@ -121,3 +134,11 @@ public sealed class ProjectionClient(HttpClient http) : IProjectionClient
     public async Task<IReadOnlyList<ProjectionEntry>> GetRegisterAsync(CancellationToken ct = default)
         => await http.GetFromJsonAsync<List<ProjectionEntry>>("register", ct) ?? [];
 }
+
+/// <summary>Calls the ACL's <c>GET /catalogi/zaaktypen</c> (S-15a). The ACL also returns each zaaktype's
+/// ZGW URL; deserializing into <see cref="BeheerZaaktype"/> keeps only the public-safe fields.</summary>
+public sealed class AclClient(HttpClient http) : IAclClient
+{
+    public async Task<IReadOnlyList<BeheerZaaktype>> GetZaaktypenAsync(CancellationToken ct = default)
+        => await http.GetFromJsonAsync<List<BeheerZaaktype>>("catalogi/zaaktypen", ct) ?? [];
+}