feat(portal-beheer): beheer portal + read-only catalogus viewer (closes #130) (#133)

## What & why

S-15a, the first of the S-15 (#16) split. A new **beheer** portal (medewerker realm, like behandel) shows the ZTC catalogus — the published zaaktypen — **read-only**. A beheerder logs in and sees the seeded BIG-REGISTRATIE zaaktype.

Closes #130

### The vertical

portal → BFF `GET /beheer/catalogi/zaaktypen` (medewerker realm + `beheerder` role) → ACL `GET /catalogi/zaaktypen` → ZGW Catalogi API.

- **ACL**: new read-only `GET /catalogi/zaaktypen` listing published zaaktypen (reuses the ADR-0021 Catalogi client; public-safe `identificatie`/`omschrijving`).
- **BFF**: new typed `IAclClient` + `Downstream:Acl:BaseUrl`, and `GET /beheer/catalogi/zaaktypen` behind a new `beheerder` policy (reuses the medewerker bearer scheme + realm-role lifting). OpenAPI spec + generated Angular client regenerated.
- **Keycloak**: `beheerder` realm role + `bram-beheerder` test user in the medewerker realm.
- **Frontend**: new `apps/beheer` Angular app (copied from behandel) with a read-only catalogus page; `SECURE_API_ROUTES=['/beheer/']`.
- **Infra**: `beheer` compose service (port 8143), added to `WAIT_SVCS` + CI log-dump; a Playwright e2e (beheerder login → catalogus shows BIG-REGISTRATIE).

### New boundary → ADR-0025

The BFF now reaches the **ACL directly** for the catalogus read — a new service-to-service edge (§14). The catalogus is neither a domain nor a projection concern, and §8.1 means only the ACL may read ZGW; routing through the domain would pollute it with a non-domain passthrough. §8.1/§8.3 stay intact. Recorded in **ADR-0025**.

## Definition of Done

- [x] Failing test committed before each implementation (red→green per layer: ACL, BFF, frontend).
- [x] Conventional Commits referencing #130.
- [ ] CI green — pending Gitea Actions run.
- [x] `docker compose up` brings up `beheer` (health-gated in `WAIT_SVCS`).
- [x] Docs — ADR-0025 + demo-script S-15a note.
- [x] Demo note in `docs/demo-script.md`.

## Verified locally

lint (`dotnet format`) ✓ · .NET unit (Acl 57 / Big 152 / EventSubscriber 19 / Bff 40) ✓ · frontend lint+test (8 projects) ✓ · frontend build (4 apps) ✓. Mutation ratchet: added a gateway unit test for the new `ListZaaktypenAsync` mapping so the ACL score holds. verify-stack (compose smoke + e2e) runs in CI.

## Notes for reviewers

- The BFF drops the ZGW URL from `BeheerZaaktype` (public-safe: identificatie + omschrijving only).
- The catalogus e2e asserts on the stable seeded `BIG-REGISTRATIE` (not a per-test reference), safe on the shared verify stack.
- Follow-ups: **S-15b** (#131) default-fill CRUD, **S-15c** (#132) medewerker-realm MFA.

🤖 Generated with [Claude Code](https://claude.com/claude-code)Reviewed-on: #133

services/acl/Acl.Api/Program.cs

@@ -85,6 +85,12 @@ app.MapPost("/documenten", async (StoreDocumentRequest body, AclService acl, Can
     return Results.Ok(new { informatieobjectUrl = url.ToString() });
 });
 
+// List the published zaaktypen — the read-only catalogus the beheer portal shows (S-15a). The BFF
+// proxies this behind medewerker-realm + beheerder authorization; the ACL trusts its callers (§8.3)
+// and is the only code allowed to read the ZGW Catalogi API (§8.1).
+app.MapGet("/catalogi/zaaktypen", async (AclService acl, CancellationToken ct) =>
+    Results.Ok(await acl.ListZaaktypenAsync(ct)));
+
 app.Run();
 
 public sealed record OpenZaakRequest(string Bsn, string Reference);

services/acl/Acl.Application/AclService.cs

@@ -42,6 +42,11 @@ public sealed class AclService(IZaakGateway gateway, AclDefaults defaults, IZaak
         await gateway.SetZaakToCancellationStatusAsync(zaakUrl, await catalog.GetZaaktypeUrlAsync(ct), clock.Today, ct);
     }
 
+    /// <summary>The published zaaktypen, for the beheer catalogus viewer (S-15a). Read-only passthrough:
+    /// no default-fill, the ACL is simply the only code allowed to read ZGW (§8.1).</summary>
+    public Task<IReadOnlyList<ZaaktypeSummary>> ListZaaktypenAsync(CancellationToken ct = default) =>
+        gateway.ListZaaktypenAsync(ct);
+
     /// <summary>The zaak's reference (its ZGW identificatie), for the read projection (#78).</summary>
     public Task<string> GetZaakReferenceAsync(Uri zaakUrl, CancellationToken ct = default)
     {

services/acl/Acl.Application/IZaakGateway.cs

@@ -40,4 +40,8 @@ public interface IZaakGateway
     /// <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);
+
+    /// <summary>List the published zaaktypen from the Catalogi API — the read-only catalogus the beheer
+    /// portal shows (S-15a). The ACL is the only code allowed to read ZGW (§8.1).</summary>
+    Task<IReadOnlyList<ZaaktypeSummary>> ListZaaktypenAsync(CancellationToken ct = default);
 }

services/acl/Acl.Application/ZaaktypeSummary.cs

@@ -0,0 +1,6 @@
+namespace Acl.Application;
+
+/// <summary>A published zaaktype as the beheer catalogus viewer shows it (S-15a). Public-safe: the
+/// business <see cref="Identificatie"/> + human <see cref="Omschrijving"/> and the ZGW <see cref="Url"/>
+/// (the URL is the ACL's own reference, not shown to end users).</summary>
+public sealed record ZaaktypeSummary(string Identificatie, string Omschrijving, Uri Url);

services/acl/Acl.Infrastructure/OpenZaakGateway.cs

@@ -170,6 +170,16 @@ public sealed class OpenZaakGateway(HttpClient http, OpenZaakOptions options) :
         return new Uri(match.Url);
     }
 
+    public async Task<IReadOnlyList<ZaaktypeSummary>> ListZaaktypenAsync(CancellationToken ct = default)
+    {
+        // Only published zaaktypen (status=definitief excludes concepts) — the read-only catalogus the
+        // beheer portal shows. Public-safe fields only.
+        var page = await GetAsync<ZaaktypePage>("/catalogi/api/v1/zaaktypen?status=definitief", "zaaktypen", ct);
+        return (page.Results ?? [])
+            .Select(z => new ZaaktypeSummary(z.Identificatie ?? "", z.Omschrijving ?? "", new Uri(z.Url)))
+            .ToList();
+    }
+
     // GETs an absolute-by-path ZGW resource with auth (no CRS — catalogi is not a geo API).
     private async Task<T> GetAsync<T>(string pathAndQuery, string label, CancellationToken ct)
     {
@@ -346,7 +356,8 @@ public sealed class OpenZaakGateway(HttpClient http, OpenZaakOptions options) :
 
     private sealed record ZaaktypeDto(
         [property: JsonPropertyName("url")] string Url,
-        [property: JsonPropertyName("identificatie")] string? Identificatie);
+        [property: JsonPropertyName("identificatie")] string? Identificatie,
+        [property: JsonPropertyName("omschrijving")] string? Omschrijving = null);
 
     private sealed record InformatieobjecttypePage(
         [property: JsonPropertyName("results")] IReadOnlyList<InformatieobjecttypeDto>? Results);

services/acl/Acl.Tests/AclServiceTests.cs

@@ -65,6 +65,14 @@ public class AclServiceTests
             ResolvedByOmschrijving = omschrijving;
             return Task.FromResult(ResolvedInformatieobjecttype);
         }
+
+        public IReadOnlyList<ZaaktypeSummary> Zaaktypen { get; } =
+        [
+            new("BIG-REGISTRATIE", "BIG-registratie", new Uri("http://openzaak/catalogi/api/v1/zaaktypen/big")),
+        ];
+
+        public Task<IReadOnlyList<ZaaktypeSummary>> ListZaaktypenAsync(CancellationToken ct = default) =>
+            Task.FromResult(Zaaktypen);
     }
 
     private static AclDefaults Defaults() => new()
@@ -225,4 +233,18 @@ public class AclServiceTests
         await Assert.ThrowsAsync<ArgumentNullException>(() => service.GetZaakReferenceAsync(null!));
         Assert.Null(gateway.ReadReferenceFor);
     }
+
+    [Fact]
+    public async Task Listing_zaaktypen_returns_the_gateways_published_zaaktypen(/* S-15a */)
+    {
+        var gateway = new FakeGateway();
+        var service = ServiceWith(gateway, Defaults(), new DateOnly(2026, 6, 4));
+
+        var zaaktypen = await service.ListZaaktypenAsync();
+
+        var only = Assert.Single(zaaktypen);
+        Assert.Equal("BIG-REGISTRATIE", only.Identificatie);
+        Assert.Equal("BIG-registratie", only.Omschrijving);
+        Assert.Equal(new Uri("http://openzaak/catalogi/api/v1/zaaktypen/big"), only.Url);
+    }
 }

services/acl/Acl.Tests/OpenZaakGatewayTests.cs

@@ -824,4 +824,51 @@ public class OpenZaakGatewayTests
         await Assert.ThrowsAnyAsync<ArgumentException>(() => Gateway(handler).ResolveZaaktypeUrlAsync(" "));
         await Assert.ThrowsAnyAsync<ArgumentException>(() => Gateway(handler).ResolveInformatieobjecttypeUrlAsync(" "));
     }
+
+    [Fact]
+    public async Task Listing_zaaktypen_queries_published_zaaktypen_and_maps_them(/* S-15a */)
+    {
+        HttpRequestMessage? seen = null;
+        var handler = new StubHandler(req =>
+        {
+            seen = req;
+            const string json = """
+                {"results":[
+                  {"url":"http://openzaak/catalogi/api/v1/zaaktypen/big","identificatie":"BIG-REGISTRATIE","omschrijving":"BIG-registratie"},
+                  {"url":"http://openzaak/catalogi/api/v1/zaaktypen/her","identificatie":"BIG-HERREGISTRATIE","omschrijving":"BIG-herregistratie"}
+                ]}
+                """;
+            return Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new StringContent(json, Encoding.UTF8, "application/json"),
+            });
+        });
+
+        var zaaktypen = await Gateway(handler).ListZaaktypenAsync();
+
+        // Only the published zaaktypen collection is queried (status=definitief excludes concepts).
+        Assert.Contains("/catalogi/api/v1/zaaktypen", seen!.RequestUri!.ToString());
+        Assert.Contains("status=definitief", seen.RequestUri!.ToString());
+        // Authenticated like the other catalogi reads.
+        Assert.Equal("Bearer", seen.Headers.Authorization!.Scheme);
+        // Each result maps to a public-safe summary (identificatie + omschrijving + url).
+        Assert.Equal(2, zaaktypen.Count);
+        Assert.Equal("BIG-REGISTRATIE", zaaktypen[0].Identificatie);
+        Assert.Equal("BIG-registratie", zaaktypen[0].Omschrijving);
+        Assert.Equal(new Uri("http://openzaak/catalogi/api/v1/zaaktypen/big"), zaaktypen[0].Url);
+        Assert.Equal("BIG-HERREGISTRATIE", zaaktypen[1].Identificatie);
+    }
+
+    [Fact]
+    public async Task Listing_zaaktypen_returns_empty_when_the_catalogus_has_none()
+    {
+        var handler = new StubHandler(_ => Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK)
+        {
+            Content = new StringContent("""{"results":[]}""", Encoding.UTF8, "application/json"),
+        }));
+
+        var zaaktypen = await Gateway(handler).ListZaaktypenAsync();
+
+        Assert.Empty(zaaktypen);
+    }
 }

services/acl/Acl.Tests/ZaaktypeCatalogTests.cs

@@ -36,6 +36,7 @@ public class ZaaktypeCatalogTests
         public Task SetZaakToCancellationStatusAsync(Uri z, Uri zt, DateOnly d, CancellationToken ct = default) => throw new NotSupportedException();
         public Task<string> GetZaakIdentificatieAsync(Uri z, CancellationToken ct = default) => throw new NotSupportedException();
         public Task<Uri> StoreDocumentAsync(DocumentRequest r, CancellationToken ct = default) => throw new NotSupportedException();
+        public Task<IReadOnlyList<ZaaktypeSummary>> ListZaaktypenAsync(CancellationToken ct = default) => throw new NotSupportedException();
     }
 
     private static AclDefaults Defaults() => new()