feat(acl): resolve zaaktype + informatieobjecttype by business key, not a pinned URL (refs #113)

The ACL now discovers its BIG zaaktype (by identificatie) and diploma
informatieobjecttype (by omschrijving) from OpenZaak's Catalogi API, instead of
being handed server-assigned URLs in config. A CachedZaaktypeCatalog resolves
lazily on first use and caches (success only, so a pre-publish miss is retried);
AclDefaults now carries ZaaktypeIdentificatie/InformatieobjecttypeOmschrijving.
Clear errors replace the opaque placeholder-URL 400. Unit tests cover the
resolver (resolve/cache/retry-on-failure) and the gateway lookups (match/miss).

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

services/acl/Acl.Application/IZaakGateway.cs

@@ -32,4 +32,12 @@ public interface IZaakGateway
     /// the created informatieobject.
     /// </summary>
     Task<Uri> StoreDocumentAsync(DocumentRequest request, CancellationToken ct = default);
+
+    /// <summary>Resolve the URL of the published zaaktype with the given <paramref name="identificatie"/>
+    /// from the Catalogi API (S-27). Throws if no published zaaktype matches.</summary>
+    Task<Uri> ResolveZaaktypeUrlAsync(string identificatie, CancellationToken ct = default);
+
+    /// <summary>Resolve the URL of the published informatieobjecttype with the given
+    /// <paramref name="omschrijving"/> from the Catalogi API (S-27). Throws if none matches.</summary>
+    Task<Uri> ResolveInformatieobjecttypeUrlAsync(string omschrijving, CancellationToken ct = default);
 }