stop emitting reaction events to chat log; badges handle display

pkg/agent/core.go

@@ -700,8 +700,6 @@ func (s *agent) ReactTo(responseID, emoji string) error {
 		s.session.Reactions = append(s.session.Reactions, reaction)
 	}
 	s.session.recomputeReactionCounts()
-	msg := "[reaction to assistant response " + responseID + ": " + category + " (" + emoji + ")] " + desc
-	s.emit(Event{Role: "user", Content: msg, ResponseID: responseID})
 	s.saveSession()
 	return nil
 }