refactor: 클라이언트 버킷 상태 모니터링 custom.inflow 패키지로 분리

- InflowTargetBucketService/Controller에서 클라이언트 관련 메서드/엔드포인트 제거
- ClientInflowTargetBucketService/Controller를 custom.inflow 패키지에 신규 생성
  (ClientInflowTargetMetricService/Controller 패턴과 일치)
- 관련 단위 테스트 추가 및 기존 테스트에서 클라이언트 케이스 제거

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

src/main/java/com/eactive/eai/custom/inflow/ClientInflowTargetBucketController.java

@@ -0,0 +1,63 @@
+package com.eactive.eai.custom.inflow;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.eactive.eai.manage.inflow.TargetBucketStatusDTO;
+
+/**
+ * 클라이언트 버킷 상태 모니터링 API.
+ *
+ * ClientDualInflowControlManager 가 활성화된 환경에서만 정상 응답한다.
+ *
+ * GET /manage/inflow/client/bucket-status             → 전체 클라이언트 버킷 상태
+ * GET /manage/inflow/client/{clientId}/bucket-status  → 특정 클라이언트 버킷 상태
+ */
+@RestController
+@RequestMapping("/manage/inflow")
+public class ClientInflowTargetBucketController {
+
+    @Autowired
+    private ClientInflowTargetBucketService bucketService;
+
+    @GetMapping("/client/bucket-status")
+    public ResponseEntity<?> getAllClientBucketStatus() {
+        List<TargetBucketStatusDTO> list = bucketService.getAllClientBucketStatus();
+        return ok(list);
+    }
+
+    @GetMapping("/client/{clientId}/bucket-status")
+    public ResponseEntity<?> getClientBucketStatus(@PathVariable String clientId) {
+        TargetBucketStatusDTO dto = bucketService.getClientBucketStatus(clientId);
+        return single(dto, "클라이언트를 찾을 수 없습니다: " + clientId);
+    }
+
+    private ResponseEntity<?> ok(List<TargetBucketStatusDTO> list) {
+        Map<String, Object> result = new HashMap<>();
+        result.put("success", true);
+        result.put("data", list);
+        result.put("count", list.size());
+        return ResponseEntity.ok(result);
+    }
+
+    private ResponseEntity<?> single(TargetBucketStatusDTO dto, String notFoundMsg) {
+        if (dto == null) {
+            Map<String, Object> error = new HashMap<>();
+            error.put("success", false);
+            error.put("message", notFoundMsg);
+            return ResponseEntity.ok(error);
+        }
+        Map<String, Object> result = new HashMap<>();
+        result.put("success", true);
+        result.put("data", dto);
+        return ResponseEntity.ok(result);
+    }
+}

src/main/java/com/eactive/eai/custom/inflow/ClientInflowTargetBucketService.java

@@ -0,0 +1,79 @@
+package com.eactive.eai.custom.inflow;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.stereotype.Service;
+
+import com.eactive.eai.common.inflow.AbstractInflowControlManager;
+import com.eactive.eai.common.inflow.InflowControlUtil;
+import com.eactive.eai.common.inflow.InflowTargetVO;
+import com.eactive.eai.common.inflow.dual.ClientDualInflowControlManager;
+import com.eactive.eai.common.inflow.dual.DualCustomBucket;
+import com.eactive.eai.manage.inflow.GroupBucketStatusDTO;
+import com.eactive.eai.manage.inflow.TargetBucketStatusDTO;
+
+/**
+ * 클라이언트 버킷 상태 조회 서비스.
+ *
+ * ClientDualInflowControlManager 가 활성화된 경우에만 동작한다.
+ */
+@Service
+public class ClientInflowTargetBucketService {
+
+    public TargetBucketStatusDTO getClientBucketStatus(String clientId) {
+        ClientDualInflowControlManager manager = getClientDualManager();
+        if (manager == null) return null;
+        DualCustomBucket bucket = manager.getClientBucket(clientId);
+        if (bucket == null) return null;
+        return toDto(clientId, "CLIENT", bucket);
+    }
+
+    public List<TargetBucketStatusDTO> getAllClientBucketStatus() {
+        ClientDualInflowControlManager manager = getClientDualManager();
+        if (manager == null) return new ArrayList<>();
+        return toDtoList("CLIENT", manager.getClientBucketMap());
+    }
+
+    protected ClientDualInflowControlManager getClientDualManager() {
+        AbstractInflowControlManager base = InflowControlUtil.getInflowControlManager();
+        return (base instanceof ClientDualInflowControlManager) ? (ClientDualInflowControlManager) base : null;
+    }
+
+    private TargetBucketStatusDTO toDto(String targetId, String targetType, DualCustomBucket bucket) {
+        InflowTargetVO vo = bucket.getInflowTargetVo();
+        List<GroupBucketStatusDTO.BucketInfo> buckets = new ArrayList<>();
+
+        if (vo.getThresholdPerSecond() > 0) {
+            long capacity  = vo.getThresholdPerSecond();
+            long available = bucket.getPerSecondAvailableTokens();
+            if (available < 0) available = capacity;
+            buckets.add(new GroupBucketStatusDTO.BucketInfo(
+                    "perSecond", capacity, Math.min(available, capacity), "SEC"));
+        }
+
+        if (vo.getThreshold() > 0) {
+            long capacity  = vo.getThreshold();
+            long available = bucket.getThresholdAvailableTokens();
+            if (available < 0) available = capacity;
+            buckets.add(new GroupBucketStatusDTO.BucketInfo(
+                    "threshold", capacity, Math.min(available, capacity), vo.getThresholdTimeUnit()));
+        }
+
+        TargetBucketStatusDTO dto = new TargetBucketStatusDTO();
+        dto.setTargetId(targetId);
+        dto.setTargetType(targetType);
+        dto.setActivate(vo.isActivate());
+        dto.setBuckets(buckets);
+        return dto;
+    }
+
+    private List<TargetBucketStatusDTO> toDtoList(String targetType, Map<String, DualCustomBucket> bucketMap) {
+        List<TargetBucketStatusDTO> result = new ArrayList<>();
+        for (Map.Entry<String, DualCustomBucket> entry : bucketMap.entrySet()) {
+            result.add(toDto(entry.getKey(), targetType, entry.getValue()));
+        }
+        return result;
+    }
+}