[PM-3530] browser extension view cache (#10437)

Introduces a way to store temporary component state, for the purposes of persisting views between extension popup open and close.

libs/angular/src/platform/services/noop-view-cache.service.ts

@@ -0,0 +1,33 @@
+import { Injectable, signal, WritableSignal } from "@angular/core";
+import type { FormGroup } from "@angular/forms";
+
+import {
+  FormCacheOptions,
+  SignalCacheOptions,
+  ViewCacheService,
+} from "../abstractions/view-cache.service";
+
+/**
+ * The functionality of the {@link ViewCacheService} is only needed in the browser extension popup,
+ * yet is provided to all clients to make sharing components easier.
+ *
+ * Non-extension clients use this noop implementation.
+ *  */
+@Injectable({
+  providedIn: "root",
+})
+export class NoopViewCacheService implements ViewCacheService {
+  /**
+   * Return a normal signal.
+   */
+  signal<T>(options: SignalCacheOptions<T>): WritableSignal<T> {
+    return signal(options.initialValue);
+  }
+
+  /**
+   * Return the original form group.
+   **/
+  formGroup<TFormGroup extends FormGroup>(options: FormCacheOptions<TFormGroup>): TFormGroup {
+    return options.control;
+  }
+}