pages loading twice poc

Cherry-picked from original branch started from Angular 13 PR

src/themes/dspace/eager-theme.module.ts

@@ -0,0 +1,53 @@
+import { NgModule } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { FormsModule } from '@angular/forms';
+import { SharedModule } from '../../app/shared/shared.module';
+import { HomeNewsComponent } from './app/home-page/home-news/home-news.component';
+import { NavbarComponent } from './app/navbar/navbar.component';
+import { HeaderComponent } from './app/header/header.component';
+import {
+  HeaderNavbarWrapperComponent
+} from './app/header-nav-wrapper/header-navbar-wrapper.component';
+import { SearchModule } from '../../app/shared/search/search.module';
+import { RootModule } from '../../app/root.module';
+import { NavbarModule } from '../../app/navbar/navbar.module';
+
+/**
+ * Add components that use a custom decorator to ENTRY_COM&PONENTS as well as DECLARATIONS. This will
+ * ensure that decorator gets picked up when the app loads
+ */
+const ENTRY_COMPONENTS = [
+];
+
+const DECLARATIONS = [
+  HomeNewsComponent,
+  HeaderComponent,
+  HeaderNavbarWrapperComponent,
+  NavbarComponent
+];
+
+@NgModule({
+  imports: [
+    CommonModule,
+    SharedModule,
+    SearchModule,
+    FormsModule,
+    RootModule,
+    NavbarModule,
+  ],
+  declarations: DECLARATIONS,
+  providers: [
+    ...ENTRY_COMPONENTS.map((component) => ({ provide: component }))
+  ]
+})
+/**
+ * This module is included in the main bundle that gets downloaded at first page load. So it should
+ * contain only the themed components that have to be available immediately for the first page load,
+ * and the minimal set of imports required to make them work. Anything you can cut from it will make
+ * the initial page load faster, but may cause the page to flicker as components that were already
+ * rendered server side need to be lazy-loaded again client side
+ *
+ * Themed EntryComponents should also be added here
+ */
+export class EagerThemeModule {
+}