Add registratie wizard, BFF dashboard-view, contracts/value-objects, and architecture docs

Checkpoint of in-progress work: the registration wizard (address prefill,
DUO diploma lookup, policy questions), decision-DTO contracts, parse-don't-
validate value objects, infrastructure adapters, plus CLAUDE.md and the
architecture/ADR docs.

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

src/app/registratie/infrastructure/big-register.adapter.ts

@@ -1,19 +1,18 @@
 import { Injectable } from '@angular/core';
 import { httpResource } from '@angular/common/http';
-import { Registration, Aantekening } from '../domain/registration';
+import { Aantekening } from '../domain/registration';
 
 /**
  * Infrastructure adapter for the BIG-register source. Exposes signal-based
  * resources (Angular's httpResource); each returns a Resource with
  * status()/value()/error()/reload(). Call from an injection context
  * (a field initializer in the store).
+ *
+ * Note: registration + person are now served via the aggregated dashboard-view
+ * endpoint (see DashboardViewAdapter). Only the notes stream remains separate.
  */
 @Injectable({ providedIn: 'root' })
 export class BigRegisterAdapter {
-  registrationResource() {
-    return httpResource<Registration>(() => 'mock/registration.json');
-  }
-
   aantekeningenResource() {
     return httpResource<Aantekening[]>(() => 'mock/notes.json', { defaultValue: [] });
   }