feat(feedback): add metric for failed label generation at ingest (#97635)

Author: vishnupsatish

src/sentry/feedback/usecases/ingest/create_feedback.py

@@ -361,6 +361,7 @@ def create_feedback_issue(
             event_fixed["tags"][f"{AI_LABEL_TAG_PREFIX}.labels"] = json.dumps(labels)
         except Exception:
             logger.exception("Error generating labels", extra={"project_id": project.id})
+            metrics.incr("feedback.label_generation.error")
 
     # Set the user.email tag since we want to be able to display user.email on the feedback UI as a tag
     # as well as be able to write alert conditions on it