feat: 클라이언트 유량제어 Command 추가 및 removeClient() 구현

- ReloadInflowClientControlCommand: 클라이언트 버킷 전체/개별 리로드
- RemoveInflowClientControlCommand: 클라이언트 버킷 제거
- DualInflowControlManager.removeClient(clientId) 메서드 추가
  (기존 removeAdapter/removeInterface와 동일한 패턴)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/main/java/com/eactive/eai/common/inflow/dual/DualInflowControlManager.java

@@ -153,6 +153,10 @@ public class DualInflowControlManager extends InflowControlManager implements Du
         reloadBucketMap(clientBucketMap, InflowType.CLIENT, clientId);
     }
 
+    public synchronized void removeClient(String clientId) {
+        clientBucketMap.remove(clientId);
+    }
+
     @Override
     public synchronized void reloadGroup() throws Exception {
         super.reloadGroup();