fix(firstleg): stop retrying deterministic completion preflight conflicts

firstleg/src/main/java/com/baiyue/firstleg/service/LoadingCompletionWorker.java

@@ -1,5 +1,6 @@
 package com.baiyue.firstleg.service;
 
+import com.baiyue.common.core.api.ResultCode;
 import com.baiyue.common.core.exception.BizException;
 import com.baiyue.firstleg.entity.LoadingCompletionCommandEntity;
 import com.baiyue.firstleg.repository.LoadingCompletionCommandRepository;
@@ -63,7 +64,13 @@ public class LoadingCompletionWorker {
     }
 
     private static boolean isDeterministicLocalBusinessFailure(String stage, Throwable cause) {
-        return cause instanceof BizException && java.util.Set.of(
+        if (!(cause instanceof BizException business)) {
+            return false;
+        }
+        if ("COMPLETED_EVENT_READY".equals(stage)) {
+            return business.getResultCode() == ResultCode.CONFLICT;
+        }
+        return java.util.Set.of(
             "OWNER_DISCOVERY", "OWNER_READY", "PLAN_GATE", "TASK_REVIEW",
             "PLAN_COMPLETE", "COMPLETED_EVENT").contains(stage);
     }