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/test/java/com/eactive/eai/manage/inflow/InflowTargetBucketControllerTest.java

@@ -18,6 +18,7 @@ import org.springframework.test.util.ReflectionTestUtils;
  *
  * <p>Spring MVC를 기동하지 않고 컨트롤러를 직접 인스턴스화하여
  * 응답 구조(success, data, count, message)를 검증한다.
+ * 클라이언트 관련 테스트는 ClientInflowTargetBucketControllerTest 에서 검증한다.
  */
 class InflowTargetBucketControllerTest {
 
@@ -148,64 +149,4 @@ class InflowTargetBucketControllerTest {
         assertEquals(Boolean.TRUE, body.get("success"));
         assertEquals(1, body.get("count"));
     }
-
-    // =========================================================================
-    // 클라이언트 — 단일 조회
-    // =========================================================================
-
-    @Test
-    void getClientBucketStatus_found_successTrueAndDataPresent() {
-        TargetBucketStatusDTO dto = makeDTO("CLIENT_A", "CLIENT");
-        when(mockService.getClientBucketStatus("CLIENT_A")).thenReturn(dto);
-
-        ResponseEntity<?> response = controller.getClientBucketStatus("CLIENT_A");
-        Map<String, Object> body = body(response);
-
-        assertEquals(200, response.getStatusCodeValue());
-        assertEquals(Boolean.TRUE, body.get("success"));
-        assertSame(dto, body.get("data"));
-        assertFalse(body.containsKey("message"));
-    }
-
-    @Test
-    void getClientBucketStatus_notFound_successFalseWithClientId() {
-        when(mockService.getClientBucketStatus("CLIENT_X")).thenReturn(null);
-
-        ResponseEntity<?> response = controller.getClientBucketStatus("CLIENT_X");
-        Map<String, Object> body = body(response);
-
-        assertEquals(Boolean.FALSE, body.get("success"));
-        assertTrue(body.get("message").toString().contains("CLIENT_X"));
-    }
-
-    // =========================================================================
-    // 클라이언트 — 전체 조회
-    // =========================================================================
-
-    @Test
-    void getAllClientBucketStatus_returnsListAndCount() {
-        List<TargetBucketStatusDTO> list = Arrays.asList(
-                makeDTO("CLIENT_A", "CLIENT"),
-                makeDTO("CLIENT_B", "CLIENT"),
-                makeDTO("CLIENT_C", "CLIENT")
-        );
-        when(mockService.getAllClientBucketStatus()).thenReturn(list);
-
-        ResponseEntity<?> response = controller.getAllClientBucketStatus();
-        Map<String, Object> body = body(response);
-
-        assertEquals(Boolean.TRUE, body.get("success"));
-        assertSame(list, body.get("data"));
-        assertEquals(3, body.get("count"));
-    }
-
-    @Test
-    void getAllClientBucketStatus_emptyList_countZero() {
-        when(mockService.getAllClientBucketStatus()).thenReturn(Collections.emptyList());
-
-        Map<String, Object> body = body(controller.getAllClientBucketStatus());
-
-        assertEquals(Boolean.TRUE, body.get("success"));
-        assertEquals(0, body.get("count"));
-    }
 }