feat(WP-67): merge behandelportal into this repo as a monorepo

Restructures into apps/ssp + apps/behandelportal (two Angular projects)
plus libs/shared + libs/beheer (cross-app libraries), replacing WP-61's
separate sibling repo. That split had already produced real drift: a
hand-vendored copy of the backend's OpenAPI doc, a shared/ui+layout tree
forked and silently diverging (7 files), and beheer + the styles.scss
token bridge duplicated byte-for-byte across both repos.

- git mv the SSP's src/app/* into apps/ssp/; fold shared/, beheer/,
  environments/, the Storybook docs/*.mdx, and styles.scss into
  libs/shared + libs/beheer (all confirmed identical between the two
  repos before merging). auth stays deliberately duplicated per
  ADR-0002 (actor-specific, expected to diverge) - amended there.
- One generated API client (libs/shared), no more vendored swagger.json.
- .dependency-cruiser split into a base factory + one config per app,
  and Storybook into .storybook-ssp/.storybook-behandelportal - both
  forced by the @auth/* alias resolving to different directories per app.
- SiteHeaderComponent/ShellComponent gained HEADER_NAV_ITEMS/
  HEADER_ADMIN_LINKS/DEBUG_PANEL injection tokens so each app supplies
  its own nav/admin-links/dev-panel instead of one being hardcoded.
- CLAUDE.md, ARCHITECTURE.md, dependencies.md, and ADR-0002 updated;
  WP-67 backlog entry documents the full decision trail.

npm run ci green (lint, dep:check x2, 360 tests across ssp/
behandelportal/shared/beheer, both localized builds, backend tests,
snippet + api-client drift); both dev servers, both Storybook
instances, and docker compose verified working.

The old sibling repo (/home/eho/repos/behandelportal) is left
untouched, not deleted.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/ssp/src/app/shell/nav.config.ts

@@ -0,0 +1,50 @@
+import { AdminLink, HeaderNavItem } from '@shared/layout/site-header/nav-config';
+import { FLAG_INSCHRIJVING_OPEN } from '@shared/domain/feature-flag';
+
+/** This app's primary nav — provided to the shared site header via HEADER_NAV_ITEMS
+    (see app.config.ts). */
+export const NAV_ITEMS: readonly HeaderNavItem[] = [
+  { label: $localize`:@@header.nav.overzicht:Overzicht`, to: '/dashboard' },
+  { label: $localize`:@@header.nav.gegevens:Mijn gegevens`, to: '/registratie' },
+  { label: $localize`:@@header.nav.herregistratie:Herregistratie`, to: '/herregistratie' },
+  {
+    label: $localize`:@@header.nav.inschrijven:Inschrijven`,
+    to: '/registreren',
+    flag: FLAG_INSCHRIJVING_OPEN,
+  },
+];
+
+/** This app's admin pages — provided to the shared site header (+ the dashboard's own
+    Beheer section) via HEADER_ADMIN_LINKS. */
+export const ADMIN_LINKS: readonly AdminLink[] = [
+  {
+    label: $localize`:@@header.nav.huisstijl:Huisstijl`,
+    description: $localize`:@@admin.link.huisstijl.desc:Organisatiesjablonen voor brieven beheren`,
+    to: '/brief/huisstijl',
+    cap: 'orgtemplate:edit',
+  },
+  {
+    label: $localize`:@@header.nav.stamdata:Stamdata`,
+    description: $localize`:@@admin.link.stamdata.desc:Business-tabellen onderhouden`,
+    to: '/beheer/stamdata',
+    cap: 'stamdata:edit',
+  },
+  {
+    label: $localize`:@@header.nav.zaken:Aanvragen`,
+    description: $localize`:@@admin.link.zaken.desc:Alle aanvragen bekijken en beheren`,
+    to: '/beheer/zaken',
+    cap: 'cases:manage',
+  },
+  {
+    label: $localize`:@@header.nav.audit:Auditlog`,
+    description: $localize`:@@admin.link.audit.desc:Toegangs- en inzagebeslissingen bekijken`,
+    to: '/beheer/audit',
+    cap: 'cases:manage',
+  },
+  {
+    label: $localize`:@@header.nav.functies:Functievlaggen`,
+    description: $localize`:@@admin.link.functies.desc:Functionaliteit aan- of uitzetten`,
+    to: '/beheer/functies',
+    cap: 'flags:manage',
+  },
+];