feat(slice scrollbar): Integrate ViewportSliceProgressScrollbar with customizations and docs (#5960)

Co-authored-by: Dan Rukas <dan.rukas@gmail.com>

extensions/cornerstone/src/services/ViewedDataService/ViewedDataService.ts

@@ -0,0 +1,58 @@
+import { PubSubService } from '@ohif/core';
+
+export type ViewedDataPayload = {
+  viewedDataId?: string;
+  viewedDataCleared?: boolean;
+};
+
+class ViewedDataService extends PubSubService {
+  public static readonly EVENTS = {
+    VIEWED_DATA_CHANGED: 'event::viewedDataChanged',
+  };
+
+  public static REGISTRATION = {
+    name: 'viewedDataService',
+    altName: 'ViewedDataService',
+    create: () => {
+      return new ViewedDataService();
+    },
+  };
+
+  private viewedDataIds = new Set<string>();
+
+  constructor() {
+    super(ViewedDataService.EVENTS);
+  }
+
+  public markDataViewed(dataId: string): void {
+    if (!dataId || this.viewedDataIds.has(dataId)) {
+      return;
+    }
+
+    this.viewedDataIds.add(dataId);
+    this._broadcastEvent(this.EVENTS.VIEWED_DATA_CHANGED, {
+      viewedDataId: dataId,
+    });
+  }
+
+  public isDataViewed(dataId: string): boolean {
+    if (!dataId) {
+      return false;
+    }
+
+    return this.viewedDataIds.has(dataId);
+  }
+
+  public clearViewedData(): void {
+    this.viewedDataIds.clear();
+    this._broadcastEvent(this.EVENTS.VIEWED_DATA_CHANGED, {
+      viewedDataCleared: true,
+    });
+  }
+
+  public subscribeViewedDataChanges(listener: (payload: ViewedDataPayload) => void) {
+    return this.subscribe(this.EVENTS.VIEWED_DATA_CHANGED, listener);
+  }
+}
+
+export default ViewedDataService;