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/shared/ui/skeleton/skeleton.component.ts

@@ -6,15 +6,15 @@ import { Component, OnDestroy, OnInit, computed, input, signal } from '@angular/
   selector: 'app-skeleton',
   styles: [`
     :host{display:block}
-    .sk{background:linear-gradient(90deg,#e8ebee 25%,#f3f5f6 37%,#e8ebee 63%);
-        background-size:400% 100%;animation:sh 1.4s ease infinite;border-radius:4px;
-        margin-block-end:0.6rem}
+    .sk{background:linear-gradient(90deg,var(--rhc-color-cool-grey-200) 25%,var(--rhc-color-cool-grey-100) 37%,var(--rhc-color-cool-grey-200) 63%);
+        background-size:400% 100%;animation:sh 1.4s ease infinite;border-radius:var(--rhc-border-radius-md);
+        margin-block-end:var(--rhc-space-max-lg)}
     @keyframes sh{0%{background-position:100% 0}100%{background-position:0 0}}
   `],
   template: `
     @if (visible()) {
       @for (l of lines(); track $index) {
-        <div class="sk" [style.width]="width()" [style.height]="height()"></div>
+        <div class="sk" aria-hidden="true" [style.width]="width()" [style.height]="height()"></div>
       }
     }
   `,