fix: review findings from full-diff audit (7 fixed)

- popularSearches sent translated display text as the actual search
  query instead of the canonical term - useSuggestion() now prefers
  target.query.q when present.
- CartService.addItem() dedup guard resolved immediately instead of
  awaiting the real in-flight add; now tracks the pending Promise per
  itemID so concurrent callers await the actual result.
- addItem()'s Promise never rejected on failure (resolve() in both
  next/error branches) - now rejects on error; buyNow() catches and
  shows an error toast instead of navigating on a failed add.
- Quick View had no stale-response guard - a slower earlier request
  could overwrite a faster later one. Added a request-generation
  counter.
- cart autoSubmitPurchase() set paymentStatus to null synchronously
  right after firing the async submit call, blanking the success
  screen while the request was still in flight. Removed the
  redundant/harmful line.
- Order terminal-status guard (cancelled/refunded can't be reopened)
  lived only in the page component. Moved enforcement into the
  gateway (single write path) via a shared TERMINAL_ORDER_STATUSES
  const, so no future caller can bypass it.
- TranslatePipe's per-instance memoization cache had no eviction,
  so bindings with volatile params (pagination counts) grew it
  unbounded for the component's lifetime. Capped at 50 entries.

Not changed: the dark-mode color override was flagged as clobbering
admin branding, but it's the exact palette explicitly requested this
session for the global dark default - not a bug.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/features/admin/orders/facade/admin-orders.facade.ts

@@ -1,6 +1,6 @@
 import { Injectable, computed, inject, signal } from '@angular/core';
 import { take } from 'rxjs/operators';
-import { AdminOrder, AdminOrderListFilters, AdminOrderStatus } from '../models/admin-order.model';
+import { AdminOrder, AdminOrderListFilters, AdminOrderStatus, TERMINAL_ORDER_STATUSES } from '../models/admin-order.model';
 import { AdminOrdersLocalGateway } from '../services/admin-orders-local.gateway';
 import { LocalStorageService } from '../../../../core/storage/local-storage.service';
 

src/app/features/admin/orders/models/admin-order.model.ts

@@ -3,6 +3,14 @@ import { UUID } from '../../../../shared/types/primitive.types';
 export type AdminOrderStatus = 'pending' | 'processing' | 'shipped' | 'delivered' | 'cancelled' | 'refunded';
 export type AdminOrderPaymentStatus = 'unpaid' | 'paid' | 'refund_requested' | 'refunded';
 
+/**
+ * Single source of truth for which statuses are terminal. Enforced at the
+ * facade layer (not just the page component's dropdown filtering) so any
+ * caller - a different admin surface, a future API route - can't move a
+ * cancelled/refunded order back to an active status.
+ */
+export const TERMINAL_ORDER_STATUSES: readonly AdminOrderStatus[] = ['cancelled', 'refunded'];
+
 export interface AdminOrderCustomer {
   name: string;
   email: string;

src/app/features/admin/orders/pages/admin-order-detail-page.component.ts

@@ -3,7 +3,7 @@ import { CommonModule } from '@angular/common';
 import { FormsModule } from '@angular/forms';
 import { ActivatedRoute, Router } from '@angular/router';
 import { AdminOrdersFacade } from '../facade/admin-orders.facade';
-import { AdminOrderStatus } from '../models/admin-order.model';
+import { AdminOrderStatus, TERMINAL_ORDER_STATUSES } from '../models/admin-order.model';
 import { TranslatePipe } from '../../../../i18n/translate.pipe';
 import { TranslateService } from '../../../../i18n/translate.service';
 import { LanguageService } from '../../../../services/language.service';
@@ -13,7 +13,6 @@ import { OrderTimelineComponent, OrderTimelineEntry } from '../components/order-
 import { ConfirmDialogComponent } from '../../../../shared/ui/confirm-dialog/confirm-dialog.component';
 
 const WORKFLOW_STEPS: AdminOrderStatus[] = ['pending', 'processing', 'shipped', 'delivered'];
-const TERMINAL_STATUSES: AdminOrderStatus[] = ['cancelled', 'refunded'];
 
 @Component({
   selector: 'app-admin-order-detail-page',
@@ -32,7 +31,7 @@ export class AdminOrderDetailPageComponent {
 
   readonly statuses: AdminOrderStatus[] = ['pending', 'processing', 'shipped', 'delivered', 'cancelled', 'refunded'];
   /** Terminal statuses are only reachable via the confirm-gated cancel()/requestRefund(), never the raw dropdown. */
-  readonly selectableStatuses: AdminOrderStatus[] = this.statuses.filter(status => !TERMINAL_STATUSES.includes(status));
+  readonly selectableStatuses: AdminOrderStatus[] = this.statuses.filter(status => !TERMINAL_ORDER_STATUSES.includes(status));
   readonly workflowSteps = WORKFLOW_STEPS;
   readonly noteDraft = signal('');
   readonly pendingCancelId = signal<string | null>(null);
@@ -41,7 +40,7 @@ export class AdminOrderDetailPageComponent {
 
   readonly isTerminal = computed(() => {
     const order = this.facade.selected();
-    return !!order && TERMINAL_STATUSES.includes(order.status);
+    return !!order && TERMINAL_ORDER_STATUSES.includes(order.status);
   });
 
   readonly currentStepIndex = computed(() => {
@@ -79,7 +78,7 @@ export class AdminOrderDetailPageComponent {
   }
 
   setStatus(id: string, status: AdminOrderStatus): void {
-    if (TERMINAL_STATUSES.includes(status)) {
+    if (TERMINAL_ORDER_STATUSES.includes(status)) {
       // Unreachable from the dropdown (options are filtered), but guard anyway
       // since terminal transitions must always go through the confirm dialog.
       return;

src/app/features/admin/orders/pages/admin-orders-list-page.component.ts

@@ -3,7 +3,7 @@ import { CommonModule } from '@angular/common';
 import { FormsModule } from '@angular/forms';
 import { Router } from '@angular/router';
 import { AdminOrdersFacade, AdminOrderColumn, ALL_ORDER_COLUMNS } from '../facade/admin-orders.facade';
-import { AdminOrderStatus } from '../models/admin-order.model';
+import { AdminOrderStatus, TERMINAL_ORDER_STATUSES } from '../models/admin-order.model';
 import { TranslatePipe } from '../../../../i18n/translate.pipe';
 import { LanguageService } from '../../../../services/language.service';
 import { ButtonComponent } from '../../../../shared/ui/button/button.component';
@@ -32,7 +32,8 @@ export class AdminOrdersListPageComponent {
 
   readonly statuses = ['all', 'pending', 'processing', 'shipped', 'delivered', 'cancelled', 'refunded'] as const;
   /** Bulk status change excludes terminal statuses - cancel/refund must go through the confirm-gated single-order flow. */
-  readonly bulkSelectableStatuses: AdminOrderStatus[] = ['pending', 'processing', 'shipped', 'delivered'];
+  readonly bulkSelectableStatuses: AdminOrderStatus[] = (['pending', 'processing', 'shipped', 'delivered'] as const)
+    .filter(status => !TERMINAL_ORDER_STATUSES.includes(status));
   readonly allColumns = ALL_ORDER_COLUMNS;
   protected readonly columnsPanelOpen = signal(false);
   protected readonly bulkStatusValue = signal<AdminOrderStatus>('pending');

src/app/features/admin/orders/services/admin-orders-local.gateway.ts

@@ -1,7 +1,7 @@
 import { Injectable, inject } from '@angular/core';
 import { Observable, of } from 'rxjs';
 import { delay } from 'rxjs/operators';
-import { AdminOrder, AdminOrderListFilters, AdminOrdersListResult, AdminOrderStatus } from '../models/admin-order.model';
+import { AdminOrder, AdminOrderListFilters, AdminOrdersListResult, AdminOrderStatus, TERMINAL_ORDER_STATUSES } from '../models/admin-order.model';
 import { AdminOrdersGateway } from './admin-orders-gateway.interface';
 import { AdminAuthService } from '../../../../core/admin-auth/admin-auth.service';
 
@@ -38,12 +38,20 @@ export class AdminOrdersLocalGateway implements AdminOrdersGateway {
   }
 
   updateStatus(id: string, status: AdminOrderStatus): Observable<AdminOrder | null> {
-    return this.mutate(id, order => ({
-      ...order,
-      status,
-      updatedAt: new Date().toISOString(),
-      timeline: [...order.timeline, { status, timestamp: new Date().toISOString(), eventKey: 'statusChanged' as const, actor: this.currentActor }],
-    }));
+    return this.mutate(id, order => {
+      // Once terminal (cancelled/refunded), an order never moves to any
+      // other status again - enforced here, not just in the admin UI, so
+      // no caller (this gateway is the single write path) can reopen one.
+      if (TERMINAL_ORDER_STATUSES.includes(order.status)) {
+        return order;
+      }
+      return {
+        ...order,
+        status,
+        updatedAt: new Date().toISOString(),
+        timeline: [...order.timeline, { status, timestamp: new Date().toISOString(), eventKey: 'statusChanged' as const, actor: this.currentActor }],
+      };
+    });
   }
 
   requestRefund(id: string): Observable<AdminOrder | null> {