Restructure into DDD bounded contexts + functional state management

Reorganise from atomic-design-only folders into bounded contexts
(auth / registratie / herregistratie) over a shared kernel, each split into
domain / application / infrastructure / ui layers. Dependencies point inward;
the domain layer is framework-free. Path aliases (@shared/@auth/@registratie/
@herregistratie) make import direction explicit.

State management (Elm-style, native TS, no new deps):
- shared/application/store.ts — createStore(init, update): pure reducer + signal
- shared/application/remote-data.ts — add map/map2/map3/andThen combinators so
  several services fold into one RemoteData; <app-async> gains an [rd] input
- registratie/application/big-profile.store.ts — root singleton combining the
  BIG-register and BRP services via map2 into one state; holds the optimistic
  herregistratie flag shared with the dashboard
- herregistratie: machine gains a WizardMsg union + pure reduce; submit is a
  command that calls infra and dispatches the result, with optimistic update +
  rollback against the shared store
- auth: SessionStore + DigiD adapter + functional route guard; login establishes
  the session, protected routes use canActivate

Rich domain: registration.policy.ts (statusColor/label, herregistratie
eligibility, invariants); BigNummer/Postcode/Uren value objects with smart
constructors. status-badge is now domain-free (colour/label inputs).

Specs for the reducer, RemoteData combinators, and eligibility policy.

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

src/app/registratie/ui/registration-summary/registration-summary.component.ts

@@ -0,0 +1,44 @@
+import { Component, input } from '@angular/core';
+import { DatePipe } from '@angular/common';
+import { Registration } from '@registratie/domain/registration';
+import { statusColor, statusLabel } from '@registratie/domain/registration.policy';
+import { DataRowComponent } from '@shared/ui/data-row/data-row.component';
+import { StatusBadgeComponent } from '@shared/ui/status-badge/status-badge.component';
+
+/** Organism: registration summary card. Composes data-row molecules + status-badge atom. */
+@Component({
+  selector: 'app-registration-summary',
+  imports: [DatePipe, DataRowComponent, StatusBadgeComponent],
+  template: `
+    <div class="rhc-card rhc-card--default">
+      <dl class="rhc-data-summary rhc-data-summary--row">
+        <app-data-row key="BIG-nummer" [value]="reg().bigNummer" />
+        <app-data-row key="Naam" [value]="reg().naam" />
+        <app-data-row key="Beroep" [value]="reg().beroep" />
+        <app-data-row key="Status">
+          <app-status-badge [label]="label()" [color]="color()" />
+        </app-data-row>
+        <app-data-row key="Registratiedatum" [value]="reg().registratiedatum | date:'longDate'" />
+        <!-- Each status variant renders only the row its own data supports. -->
+        @switch (reg().status.tag) {
+          @case ('Geregistreerd') {
+            <app-data-row key="Uiterste herregistratie" [value]="$any(reg().status).herregistratieDatum | date:'longDate'" />
+          }
+          @case ('Geschorst') {
+            <app-data-row key="Geschorst tot" [value]="$any(reg().status).geschorstTot | date:'longDate'" />
+            <app-data-row key="Reden" [value]="$any(reg().status).reden" />
+          }
+          @case ('Doorgehaald') {
+            <app-data-row key="Doorgehaald op" [value]="$any(reg().status).doorgehaaldOp | date:'longDate'" />
+            <app-data-row key="Reden" [value]="$any(reg().status).reden" />
+          }
+        }
+      </dl>
+    </div>
+  `,
+})
+export class RegistrationSummaryComponent {
+  reg = input.required<Registration>();
+  protected label = () => statusLabel(this.reg().status.tag);
+  protected color = () => statusColor(this.reg().status.tag);
+}