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

apps/beheer/src/app/app.config.ts

@@ -0,0 +1,39 @@
+import { provideHttpClient, withInterceptors } from '@angular/common/http';
+import { ApplicationConfig, provideBrowserGlobalErrorListeners } from '@angular/core';
+import { provideRouter } from '@angular/router';
+import { authInterceptor, provideMedewerkerAuth } from 'auth';
+import { appRoutes } from './app.routes';
+
+/** Environment-specific settings fetched from /config.json at startup (see main.ts). */
+export interface RuntimeConfig {
+  /** The Keycloak `medewerker` realm issuer as the browser reaches it (dev: localhost; compose: keycloak:8080). */
+  authority: string;
+}
+
+/**
+ * Route prefixes whose requests carry the medewerker token. These MUST match the **relative** URLs
+ * the api-client actually calls (same-origin via the nginx proxy) — the interceptor matches on
+ * `req.url`, which stays relative, so an absolute origin would never match and the token would go
+ * unattached. Only `/beheer/` is secured; the app calls no other endpoint group.
+ */
+export const SECURE_API_ROUTES = ['/beheer/'];
+
+/**
+ * Build the app providers from runtime config. `redirectUrl` is the app's own origin (where Keycloak
+ * redirects back). `secureRoutes` uses {@link SECURE_API_ROUTES} — relative prefixes, not the origin.
+ */
+export function appConfig(runtime: RuntimeConfig): ApplicationConfig {
+  const origin = typeof window !== 'undefined' ? window.location.origin : '/';
+  return {
+    providers: [
+      provideBrowserGlobalErrorListeners(),
+      provideRouter(appRoutes),
+      provideHttpClient(withInterceptors([authInterceptor()])),
+      provideMedewerkerAuth({
+        authority: runtime.authority,
+        redirectUrl: origin,
+        secureRoutes: SECURE_API_ROUTES,
+      }),
+    ],
+  };
+}