Step 1: i18n foundation (@angular/localize) + data inventory

Domain reference data already lives in the backend (per ADR-0001); the only
residual "move" was ~90 inlined Dutch UI strings with no i18n layer.

- Wire @angular/localize ($localize) — Angular first-party, no third-party lib
- Pin the pattern on shared/ui/async: Dutch fallbacks → language-agnostic
  input()s with localizable $localize defaults (English-shared-UI rule)
- CLAUDE.md: drop i18n (now in scope) + stale "real backend"/"OpenAPI codegen"
  (both already shipped); document the $localize convention

Bulk string sweep deferred to Step 2 to avoid touching ~36 files twice.

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

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

@@ -46,15 +46,15 @@ export class AsyncErrorDirective {
           <ng-container [ngTemplateOutlet]="errorTpl()!.tpl"
             [ngTemplateOutletContext]="{ $implicit: error(), retry: retry }" />
         } @else {
-          <app-alert type="error">Er ging iets mis bij het laden van de gegevens.</app-alert>
+          <app-alert type="error">{{ errorText() }}</app-alert>
           <div style="margin-top:1rem">
-            <app-button variant="secondary" (click)="retry()">Opnieuw proberen</app-button>
+            <app-button variant="secondary" (click)="retry()">{{ retryText() }}</app-button>
           </div>
         }
       }
       @case ('Empty') {
         @if (emptyTpl()) { <ng-container [ngTemplateOutlet]="emptyTpl()!.tpl" /> }
-        @else { <p class="rhc-paragraph">Geen gegevens gevonden.</p> }
+        @else { <p class="rhc-paragraph">{{ emptyText() }}</p> }
       }
       @case ('Success') {
         <ng-container [ngTemplateOutlet]="loadedTpl().tpl"
@@ -72,6 +72,12 @@ export class AsyncComponent<T> {
   data = input<RemoteData<Error | undefined, T>>();
   isEmpty = input<(v: T) => boolean>(() => false);
 
+  // Shared/English component: copy lives behind language-agnostic inputs. Defaults are
+  // localizable via $localize (source = default locale, currently nl); callers may override.
+  errorText = input($localize`:@@async.error:Er ging iets mis bij het laden van de gegevens.`);
+  retryText = input($localize`:@@async.retry:Opnieuw proberen`);
+  emptyText = input($localize`:@@async.empty:Geen gegevens gevonden.`);
+
   loadedTpl = contentChild.required(AsyncLoadedDirective);
   loadingTpl = contentChild(AsyncLoadingDirective);
   emptyTpl = contentChild(AsyncEmptyDirective);