fix(dirt): add subscription cleanup and remove dead code

Critical fixes for production code quality and memory leak prevention:

**Subscription Cleanup (ADR-0003 Compliance):**
- Add takeUntil pattern to AllActivitiesService subscriptions
- Add _destroy$ Subject and destroy() method
- Prevents memory leaks by properly unsubscribing from observables
- Follows Observable Data Services ADR requirements

**Code Quality Improvements:**
- Remove unused 'isSaving' variable from AllActivityComponent
- Remove unused 'finalize' import
- Add comment explaining error is already logged upstream
- Cleaner, more maintainable code

This ensures proper resource cleanup and follows Bitwarden's
architectural decision records for observable management.

Related to PM-27284

bitwarden_license/bit-common/src/dirt/reports/risk-insights/services/view/all-activities.service.ts

@@ -1,4 +1,5 @@
-import { BehaviorSubject } from "rxjs";
+import { BehaviorSubject, Subject } from "rxjs";
+import { takeUntil } from "rxjs/operators";
 
 import { ApplicationHealthReportDetailEnriched } from "../../models";
 import { OrganizationReportSummary } from "../../models/report-models";
@@ -11,6 +12,8 @@ export class AllActivitiesService {
   /// Going forward, this class can be simplified by using the RiskInsightsDataService
   /// as it contains the application summary data.
 
+  private _destroy$ = new Subject<void>();
+
   private reportSummarySubject$ = new BehaviorSubject<OrganizationReportSummary>({
     totalMemberCount: 0,
     totalCriticalMemberCount: 0,
@@ -40,7 +43,7 @@ export class AllActivitiesService {
 
   constructor(private dataService: RiskInsightsDataService) {
     // All application summary changes
-    this.dataService.enrichedReportData$.subscribe((report) => {
+    this.dataService.enrichedReportData$.pipe(takeUntil(this._destroy$)).subscribe((report) => {
       if (report) {
         this.setAllAppsReportSummary(report.summaryData);
         this.setAllAppsReportDetails(report.reportData);
@@ -48,14 +51,14 @@ export class AllActivitiesService {
     });
 
     // Critical application summary changes
-    this.dataService.criticalReportResults$.subscribe((report) => {
+    this.dataService.criticalReportResults$.pipe(takeUntil(this._destroy$)).subscribe((report) => {
       if (report) {
         this.setCriticalAppsReportSummary(report.summaryData);
       }
     });
 
     // New applications changes (from orchestrator's reactive pipeline)
-    this.dataService.newApplications$.subscribe((newApps) => {
+    this.dataService.newApplications$.pipe(takeUntil(this._destroy$)).subscribe((newApps) => {
       this.setNewApplications(newApps);
     });
   }
@@ -108,4 +111,13 @@ export class AllActivitiesService {
       newApplications: newApps,
     });
   }
+
+  /**
+   * Cleanup method to unsubscribe from all observables.
+   * Should be called when the service is destroyed to prevent memory leaks.
+   */
+  destroy(): void {
+    this._destroy$.next();
+    this._destroy$.complete();
+  }
 }

bitwarden_license/bit-web/src/app/dirt/access-intelligence/activity/all-activity.component.ts

@@ -2,7 +2,6 @@ import { Component, DestroyRef, inject, OnInit } from "@angular/core";
 import { takeUntilDestroyed } from "@angular/core/rxjs-interop";
 import { ActivatedRoute } from "@angular/router";
 import { firstValueFrom } from "rxjs";
-import { finalize } from "rxjs/operators";
 
 import {
   AllActivitiesService,
@@ -99,15 +98,7 @@ export class AllActivityComponent implements OnInit {
 
     if (result?.saved) {
       // User clicked Continue - save review status and critical flags
-      let isSaving = true;
-
-      firstValueFrom(
-        this.dataService.saveApplicationReviewStatus(result.selectedApplications).pipe(
-          finalize(() => {
-            isSaving = false;
-          }),
-        ),
-      )
+      firstValueFrom(this.dataService.saveApplicationReviewStatus(result.selectedApplications))
         .then(() => {
           // Success - data will update automatically through reactive pipeline
           if (result.selectedApplications.length > 0) {
@@ -127,7 +118,8 @@ export class AllActivityComponent implements OnInit {
             });
           }
         })
-        .catch((error) => {
+        .catch(() => {
+          // Error already logged by orchestrator service
           this.toastService.showToast({
             variant: "error",
             title: this.i18nService.t("error"),