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.stories.ts

@@ -0,0 +1,30 @@
+import type { Meta, StoryObj } from '@storybook/angular';
+import { RegistrationSummaryComponent } from './registration-summary.component';
+import { Registration } from '@registratie/domain/registration';
+
+const base = {
+  bigNummer: '19012345601',
+  naam: 'Dr. A. (Anna) de Vries',
+  beroep: 'Arts',
+  registratiedatum: '2012-09-01',
+  geboortedatum: '1985-03-14',
+} satisfies Omit<Registration, 'status'>;
+
+const meta: Meta<RegistrationSummaryComponent> = {
+  title: 'Organisms/Registration Summary',
+  component: RegistrationSummaryComponent,
+};
+export default meta;
+type Story = StoryObj<RegistrationSummaryComponent>;
+
+// Each story feeds a different union variant; the card renders only the rows
+// that variant's data supports (note Doorgehaald has no herregistratie date).
+export const Geregistreerd: Story = {
+  args: { reg: { ...base, status: { tag: 'Geregistreerd', herregistratieDatum: '2027-09-01' } } },
+};
+export const Geschorst: Story = {
+  args: { reg: { ...base, status: { tag: 'Geschorst', geschorstTot: '2026-12-31', reden: 'Lopend tuchtonderzoek' } } },
+};
+export const Doorgehaald: Story = {
+  args: { reg: { ...base, status: { tag: 'Doorgehaald', doorgehaaldOp: '2024-05-01', reden: 'Op eigen verzoek' } } },
+};