Implement limb fixation exam flow

Assets/Scripts/Interaction/PingClickHandler.cs

@@ -171,12 +171,16 @@ public class PingClickHandler : MonoBehaviour
             
             var sm = FindObjectOfType<StepManager>();
             if (sm != null) sm.RecordPingStep(pingIndex, false);
+            var examMgr = FindObjectOfType<ExamFlowManager>();
+            if (examMgr != null) examMgr.OnObjectClicked(this);
         }
         else
         {
             if (chanraoObject != null) { chanraoObject.SetActive(true); Debug.Log($"[PingClick] {name} → {chanraoObject.name}"); }
             HideSelf();
             ActionHistory.Push(ActionHistory.ActionType.PingSecond, this);
+            var examMgr = FindObjectOfType<ExamFlowManager>();
+            if (examMgr != null) examMgr.OnObjectClicked(this);
             var sm = FindObjectOfType<StepManager>();
             if (sm != null) sm.RecordPingStep(pingIndex, true);
             
@@ -188,11 +192,14 @@ public class PingClickHandler : MonoBehaviour
                     remaining++;
             }
             
+            bool isExam = GameManager.Instance != null && GameManager.Instance.CurrentMode == ExperimentMode.Exam;
             if (remaining == 0)
             {
                 if (!_hasPlayedFinishVoice)
                 {
                     _hasPlayedFinishVoice = true;
+                    if (isExam) return;
+
                     Debug.Log("[PingClick] 所有的 ping 都已经绑成 chanrao 了！播放完成语音。");
                     var am = FindObjectOfType<AudioManager>();
                     if (am != null)