phase-7: add reusable input-output widget library and default registry

src/app/widgets/registry/widget-registry.bootstrap.service.ts

@@ -0,0 +1,16 @@
+import { Injectable } from '@angular/core';
+import { HeroWidgetComponent, FooterNavigationWidgetComponent, ProductCarouselWidgetComponent } from '../ui';
+import { WidgetRegistryService } from './widget-registry.service';
+
+@Injectable({ providedIn: 'root' })
+export class WidgetRegistryBootstrapService {
+  constructor(private readonly registry: WidgetRegistryService) {}
+
+  registerDefaults(): void {
+    this.registry.registerMany([
+      { type: 'hero', version: '1.0.0', component: HeroWidgetComponent },
+      { type: 'footer-navigation', version: '1.0.0', component: FooterNavigationWidgetComponent },
+      { type: 'product-carousel', version: '1.0.0', component: ProductCarouselWidgetComponent }
+    ]);
+  }
+}