Rijkshuisstijl restyle + wizard fixes

Chrome: two-tier Rijksoverheid header (white brand bar + lint-blue
breadcrumb bar, route-driven), dark multi-column footer, white page
surface. Session shown via a shared SESSION_PORT token (keeps shared/
free of the auth context).

Overview ("Mijn overzicht") rebuilt to the NL Design System #392 pattern:
side-nav + "Wat moet ik regelen" task list (derived) + "Mijn registratie"
cards. New shared components: card, task-list, side-nav; pure
tasksFromProfile (+spec).

Wizards: grey form panel, connected numbered stepper, form-field
"(verplicht)" markers + styled description/error, full-width inputs.
Propagated to login, detail, change-request, address-fields.

Bug fixes:
- wizard-shell: add FormsModule so NgForm intercepts submit (wizards now
  advance; no native GET leaking choices into the URL).
- wizard-shell: error-summary links focus the field instead of navigating
  (a fragment href resolved against <base href="/"> reloaded to "/" and
  bounced to login).
- wizard-shell: error-summary focus only on the rising edge, so typing
  while errors are shown no longer scrolls the page up.

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

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

@@ -0,0 +1,32 @@
+import { Component, input } from '@angular/core';
+import { HeadingComponent } from '@shared/ui/heading/heading.component';
+
+/** Molecule: a content card. Standardises the repeated card surface (white,
+    subtle border, rounded, padded) so pages compose cards instead of hand-rolling
+    `<div class="rhc-card">`. Optional heading; the rest is projected. */
+@Component({
+  selector: 'app-card',
+  imports: [HeadingComponent],
+  styles: [`
+    :host{display:block;block-size:100%}
+    .card{
+      background:var(--rhc-color-wit);
+      border:var(--rhc-border-width-sm) solid var(--rhc-color-border-subtle);
+      border-radius:var(--rhc-border-radius-md);
+      padding:var(--rhc-space-max-xl);
+      block-size:100%;
+      box-sizing:border-box;
+    }
+    .card > * + *{margin-block-start:var(--rhc-space-max-md)}
+  `],
+  template: `
+    <section class="card">
+      @if (heading()) { <app-heading [level]="level()">{{ heading() }}</app-heading> }
+      <ng-content />
+    </section>
+  `,
+})
+export class CardComponent {
+  heading = input<string>();
+  level = input<1 | 2 | 3 | 4 | 5>(3);
+}