fix(patch): cherry-pick 9a74271 to release/v0.33.0-preview.8-pr-21236 [CONFLICTS] (#21788)

Co-authored-by: Gaurav <39389231+gsquared94@users.noreply.github.com>
Co-authored-by: galz10 <galzahavi@google.com>

packages/core/src/code_assist/server.ts

@@ -47,7 +47,9 @@ import {
   isOverageEligibleModel,
   shouldAutoUseCredits,
 } from '../billing/billing.js';
+
 import { logBillingEvent } from '../telemetry/loggers.js';
+import { coreEvents } from '../utils/events.js';
 import { CreditsUsedEvent } from '../telemetry/billingEvents.js';
 import type {
   CaCountTokenResponse,
@@ -102,6 +104,11 @@ export class CodeAssistServer implements ContentGenerator {
     const modelIsEligible = isOverageEligibleModel(req.model);
     const shouldEnableCredits = modelIsEligible && autoUse;
 
+    if (shouldEnableCredits && !this.config?.getCreditsNotificationShown()) {
+      this.config?.setCreditsNotificationShown(true);
+      coreEvents.emitFeedback('info', 'Using AI Credits for this request.');
+    }
+
     const enabledCreditTypes = shouldEnableCredits
       ? ([G1_CREDIT_TYPE] as string[])
       : undefined;