Address review: clear Sentry user on opt-out, stub getUserId in jest mock

- Clear the per-install user id (Sentry.setUser(null)) before Sentry.close
  on data-sharing opt-out. Sentry.close may still report (anonymized) until
  the next refresh; without this those reports would keep the id attached.
- Add getUserId to the helpers/metrics jest mock in setupTests so rendering
  ErrorTracking under test doesn't call an undefined mock.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: piyalbasu

config/jest/setupTests.tsx

@@ -79,6 +79,7 @@ jest.mock("helpers/metrics", () => ({
   registerHandler: () => {},
   emitMetric: () => {},
   initAmplitude: () => {},
+  getUserId: () => "test-user-id",
   metricsMiddleware: jest.fn(
     () => () => (next: any) => (action: any) => next(action),
   ),

extension/src/popup/components/ErrorTracking/index.tsx

@@ -56,11 +56,15 @@ export const ErrorTracking = () => {
   }
 
   if (!isDataSharingAllowed) {
-    /* 
-    Note: Sentry.close does not completely disable calls to Sentry. Sentry will still report, but with a completely anonymized payload. 
+    /*
+    Note: Sentry.close does not completely disable calls to Sentry. Sentry will still report, but with a completely anonymized payload.
     When you refresh/reopen the app after disabling tracking, it will not initialize Sentry, thus disabling *all* calls to Sentry
     */
 
+    // Clear the per-install user id before closing. Sentry.close may still
+    // report (anonymized) until the next refresh; without this, those reports
+    // would keep the user id attached and defeat the anonymization.
+    Sentry.setUser(null);
     Sentry.close(500);
   }