feat(design): re-theme to CIBG Huisstijl (Bootstrap 5.2), replacing RHC/Utrecht

The portal now adheres to the CIBG design system (designsystem.cibg.nl) — a customized
Bootstrap 5.2 build — replacing the Rijkshuisstijl-Community / Utrecht theme. See ADR-0003.

- Vendor @cibg/huisstijl@3.22.0 under public/cibg-huisstijl/, loaded via a <link> in
  index.html (Storybook serves it via staticDirs). Drop the two @rijkshuisstijl-community deps.
- Token bridge in styles.scss: redefine the app's ~54 --rhc-* tokens onto CIBG/--bs-* values,
  so components keep referencing tokens (no 300+ site rewrite). System-font stack; licensed
  RO/Rijks text fonts intentionally not shipped.
- Re-skin every shared atom to Bootstrap/CIBG classes (btn, form-control, form-check-*,
  table, breadcrumb, …) keeping their input() APIs. alert is hand-rolled (CIBG drops .alert);
  local .card/.badge renamed to avoid Bootstrap collisions.
- Domain pages: drop stray rhc-*/utrecht-* classes; registration-table → table table-striped.

Verified: build green, check:tokens OK, lint clean, 174 tests pass, build-storybook OK,
and the served build loads the vendored CSS (200, .btn-primary present).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/shared/ui/checkbox/checkbox.component.ts

@@ -8,11 +8,12 @@ import { ControlValueAccessor, NG_VALUE_ACCESSOR } from '@angular/forms';
   styles: [`
     :host{display:block}
     label{display:inline-flex;align-items:center;gap:var(--rhc-space-max-md);cursor:pointer}
-    input{inline-size:1.1rem;block-size:1.1rem}
+    /* form-check-input floats/margins for the .form-check layout; here it's flex-aligned. */
+    .form-check-input{margin:0;float:none;inline-size:1.1rem;block-size:1.1rem}
   `],
   template: `
-    <label>
-      <input type="checkbox" [id]="checkboxId()" [checked]="value" [disabled]="disabled"
+    <label class="form-check-label">
+      <input class="form-check-input" type="checkbox" [id]="checkboxId()" [checked]="value" [disabled]="disabled"
         (change)="onToggle($event)" (blur)="onTouched()" />
       <span>{{ label() }}</span>
     </label>