feat(admin): 제품 사용이력 + 환자 최근처방 모달 기능

- GET /api/products/<drug_code>/usage-history
  - 제품별 처방 이력 조회 (환자명, 수량, 횟수, 일수, 총투약량)
  - 페이지네이션 + 기간 필터 지원

- GET /api/patients/<cus_code>/recent-prescriptions
  - 환자 최근 6개월 처방 내역
  - 약품별 분류(CD_MC.PRINT_TYPE) 표시 (당뇨치료, 고지혈치료 등)

- admin_products.html 모달 2개 추가
  - 제품명 클릭 → 사용이력 모달 (횟수 포함 정확한 총투약량)
  - 환자명 클릭 → 최근처방 모달 (z-index 2100으로 위에 표시)

DB 조인:
- PS_main.PreSerial = PS_sub_pharm.PreSerial
- CD_GOODS + CD_MC (PRINT_TYPE 분류)

backend/app.py

@@ -3872,6 +3872,238 @@ def api_drug_purchase_history(drug_code):
         return jsonify({'success': False, 'error': str(e)}), 500
 
 
+# ==================== 처방 사용이력 API ====================
+
+@app.route('/api/products/<drug_code>/usage-history')
+def api_product_usage_history(drug_code):
+    """
+    제품 처방 사용이력 조회 API
+    - PS_main + PS_sub_pharm JOIN
+    - 페이지네이션, 기간 필터 지원
+    - 환자명 마스킹 처리
+    """
+    page = int(request.args.get('page', 1))
+    per_page = int(request.args.get('per_page', 20))
+    months = int(request.args.get('months', 12))
+    
+    offset = (page - 1) * per_page
+    
+    try:
+        pres_session = db_manager.get_session('PM_PRES')
+        
+        # 기간 계산 (N개월 전부터)
+        from datetime import datetime, timedelta
+        start_date = (datetime.now() - timedelta(days=months * 30)).strftime('%Y%m%d')
+        
+        # 총 건수 조회 (COUNT)
+        count_result = pres_session.execute(text("""
+            SELECT COUNT(*) as total_count
+            FROM PS_sub_pharm sp
+            JOIN PS_main pm ON pm.PreSerial = sp.PreSerial
+            WHERE sp.DrugCode = :drug_code
+              AND pm.Indate >= :start_date
+              AND (sp.PS_Type IS NULL OR sp.PS_Type != '9')
+        """), {'drug_code': drug_code, 'start_date': start_date})
+        total_count = count_result.fetchone()[0]
+        
+        # 데이터 조회 (페이지네이션)
+        data_result = pres_session.execute(text("""
+            SELECT 
+                pm.Paname as patient_name,
+                pm.CusCode as cus_code,
+                pm.Indate as rx_date,
+                sp.QUAN as quantity,
+                sp.QUAN_TIME as times,
+                sp.Days as days
+            FROM PS_sub_pharm sp
+            JOIN PS_main pm ON pm.PreSerial = sp.PreSerial
+            WHERE sp.DrugCode = :drug_code
+              AND pm.Indate >= :start_date
+              AND (sp.PS_Type IS NULL OR sp.PS_Type != '9')
+            ORDER BY pm.Indate DESC
+            OFFSET :offset ROWS
+            FETCH NEXT :per_page ROWS ONLY
+        """), {
+            'drug_code': drug_code, 
+            'start_date': start_date,
+            'offset': offset,
+            'per_page': per_page
+        })
+        
+        items = []
+        for row in data_result.fetchall():
+            patient_name = row.patient_name or ''
+            cus_code = row.cus_code or ''
+            
+            # 날짜 포맷팅 (YYYYMMDD -> YYYY-MM-DD)
+            rx_date = row.rx_date or ''
+            if len(rx_date) == 8:
+                rx_date = f"{rx_date[:4]}-{rx_date[4:6]}-{rx_date[6:8]}"
+            
+            quantity = int(row.quantity) if row.quantity else 1
+            times = int(row.times) if row.times else 1  # 횟수 (QUAN_TIME)
+            days = int(row.days) if row.days else 1
+            total_dose = quantity * times * days  # 수량 × 횟수 × 일수
+            
+            items.append({
+                'patient_name': patient_name,
+                'cus_code': cus_code,
+                'rx_date': rx_date,
+                'quantity': quantity,
+                'times': times,
+                'days': days,
+                'total_dose': total_dose
+            })
+        
+        # 약품명 조회
+        drug_session = db_manager.get_session('PM_DRUG')
+        name_result = drug_session.execute(text("""
+            SELECT GoodsName FROM CD_GOODS WHERE DrugCode = :drug_code
+        """), {'drug_code': drug_code})
+        name_row = name_result.fetchone()
+        product_name = name_row[0] if name_row else drug_code
+        
+        # 총 페이지 수 계산
+        total_pages = (total_count + per_page - 1) // per_page
+        
+        return jsonify({
+            'success': True,
+            'product_name': product_name,
+            'pagination': {
+                'page': page,
+                'per_page': per_page,
+                'total_count': total_count,
+                'total_pages': total_pages
+            },
+            'items': items
+        })
+        
+    except Exception as e:
+        logging.error(f"사용이력 조회 오류: {e}")
+        return jsonify({'success': False, 'error': str(e)}), 500
+
+
+@app.route('/api/patients/<cus_code>/recent-prescriptions')
+def api_patient_recent_prescriptions(cus_code):
+    """
+    환자 최근 처방 내역 조회 API
+    - 해당 환자가 최근에 어떤 약을 처방받았는지 확인
+    - DB 부담 최소화: 최근 6개월, 최대 30건
+    """
+    try:
+        pres_session = db_manager.get_session('PM_PRES')
+        drug_session = db_manager.get_session('PM_DRUG')
+        
+        # 최근 6개월
+        from datetime import datetime, timedelta
+        start_date = (datetime.now() - timedelta(days=180)).strftime('%Y%m%d')
+        
+        # 환자의 최근 처방전 조회 (최대 10건)
+        rx_result = pres_session.execute(text("""
+            SELECT TOP 10
+                pm.PreSerial,
+                pm.Paname as patient_name,
+                pm.Indate as rx_date,
+                pm.Drname as doctor_name,
+                pm.OrderName as hospital_name
+            FROM PS_main pm
+            WHERE pm.CusCode = :cus_code
+              AND pm.Indate >= :start_date
+            ORDER BY pm.Indate DESC
+        """), {'cus_code': cus_code, 'start_date': start_date})
+        
+        prescriptions = []
+        for rx in rx_result.fetchall():
+            # 날짜 포맷팅
+            rx_date = rx.rx_date or ''
+            if len(rx_date) == 8:
+                rx_date = f"{rx_date[:4]}-{rx_date[4:6]}-{rx_date[6:8]}"
+            
+            # 해당 처방의 약품 목록 조회
+            items_result = pres_session.execute(text("""
+                SELECT 
+                    sp.DrugCode,
+                    sp.QUAN as quantity,
+                    sp.QUAN_TIME as times,
+                    sp.Days as days
+                FROM PS_sub_pharm sp
+                WHERE sp.PreSerial = :pre_serial
+                  AND (sp.PS_Type IS NULL OR sp.PS_Type != '9')
+            """), {'pre_serial': rx.PreSerial})
+            
+            # 먼저 모든 약품 데이터를 리스트로 가져오기
+            raw_items = items_result.fetchall()
+            drug_codes = [item.DrugCode for item in raw_items]
+            
+            # 약품명 + 성분명 + 분류(PRINT_TYPE) 일괄 조회
+            drug_info_map = {}
+            if drug_codes:
+                placeholders = ','.join([f"'{dc}'" for dc in drug_codes])
+                name_result = drug_session.execute(text(f"""
+                    SELECT g.DrugCode, g.GoodsName, s.SUNG_HNM, m.PRINT_TYPE
+                    FROM CD_GOODS g
+                    LEFT JOIN CD_SUNG s ON g.SUNG_CODE = s.SUNG_CODE
+                    LEFT JOIN CD_MC m ON g.DrugCode = m.DRUGCODE
+                    WHERE g.DrugCode IN ({placeholders})
+                """))
+                for row in name_result.fetchall():
+                    drug_info_map[row[0]] = {
+                        'name': row[1], 
+                        'ingredient': row[2] or '',
+                        'category': row[3] or ''  # 분류 (알러지질환약 등)
+                    }
+            
+            items = []
+            for item in raw_items:
+                info = drug_info_map.get(item.DrugCode, {})
+                drug_name = info.get('name', item.DrugCode)
+                ingredient = info.get('ingredient', '')
+                category = info.get('category', '')  # 분류 (알러지질환약 등)
+                
+                quantity = int(item.quantity) if item.quantity else 1
+                times = int(item.times) if item.times else 1
+                days = int(item.days) if item.days else 1
+                
+                items.append({
+                    'drug_code': item.DrugCode,
+                    'drug_name': drug_name,
+                    'category': category,  # 분류 추가
+                    'quantity': quantity,
+                    'times': times,
+                    'days': days,
+                    'total_dose': quantity * times * days
+                })
+            
+            prescriptions.append({
+                'pre_serial': rx.PreSerial,
+                'rx_date': rx_date,
+                'doctor_name': rx.doctor_name or '',
+                'hospital_name': rx.hospital_name or '',
+                'items': items
+            })
+        
+        # 환자명
+        patient_name = prescriptions[0]['items'][0]['drug_name'] if prescriptions else ''
+        if prescriptions and pres_session.execute(text("""
+            SELECT TOP 1 Paname FROM PS_main WHERE CusCode = :cus_code
+        """), {'cus_code': cus_code}).fetchone():
+            patient_name = pres_session.execute(text("""
+                SELECT TOP 1 Paname FROM PS_main WHERE CusCode = :cus_code
+            """), {'cus_code': cus_code}).fetchone()[0]
+        
+        return jsonify({
+            'success': True,
+            'cus_code': cus_code,
+            'patient_name': patient_name,
+            'prescription_count': len(prescriptions),
+            'prescriptions': prescriptions
+        })
+        
+    except Exception as e:
+        logging.error(f"환자 처방 조회 오류: {e}")
+        return jsonify({'success': False, 'error': str(e)}), 500
+
+
 # ==================== 위치 정보 API ====================
 
 @app.route('/api/locations')