Reduce computing lock TTL from 600s to 300s for auto-expiry safety

Author: patrick91

backend/reviews/admin.py

@@ -470,9 +470,10 @@ def review_recap_compute_analysis_view(self, request, review_session_id):
             if cached_result is not None:
                 return JsonResponse(cached_result)
 
-        # Use cache.add as a lock to prevent duplicate task dispatch
+        # Use cache.add as a lock to prevent duplicate task dispatch.
+        # Short TTL so lock auto-expires if the worker is killed before cleanup.
         computing_key = f"{combined_cache_key}:computing"
-        if cache.add(computing_key, True, timeout=600):
+        if cache.add(computing_key, True, timeout=300):
             compute_recap_analysis.apply_async(
                 args=[conference.id, combined_cache_key],
                 kwargs={"force_recompute": force_recompute},