feat(purchase): 구매 취소/반품 + 입고일 기준 월별 분석

- 상태 추가: cancelled(구매취소), returned(반품)
- API: PUT /:id/cancel, /:id/return, /:id/revert-cancel
- 데스크탑: 구매완료→취소 버튼, 입고완료→반품 버튼, 취소→되돌리기
- 분석 페이지: 구매일/입고일 기준 전환 토글, 입고일 기준 월간 분류 집계 + 입고 목록
- Settlement API: GET /received-summary, /received-list (입고일 기준)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

system1-factory/web/static/js/purchase-request-mobile.js

@@ -4,8 +4,8 @@ const TKUSER_BASE_URL = location.hostname.includes('technicalkorea.net')
     : location.protocol + '//' + location.hostname + ':30180';
 
 const CAT_LABELS = { consumable: '소모품', safety: '안전용품', repair: '수선비', equipment: '설비' };
-const STATUS_LABELS = { pending: '대기', grouped: '구매진행중', purchased: '구매완료', received: '입고완료', hold: '보류' };
-const STATUS_COLORS = { pending: 'badge-amber', grouped: 'badge-blue', purchased: 'badge-green', received: 'badge-teal', hold: 'badge-gray' };
+const STATUS_LABELS = { pending: '대기', grouped: '구매진행중', purchased: '구매완료', received: '입고완료', cancelled: '취소', returned: '반품', hold: '보류' };
+const STATUS_COLORS = { pending: 'badge-amber', grouped: 'badge-blue', purchased: 'badge-green', received: 'badge-teal', cancelled: 'badge-red', returned: 'badge-red', hold: 'badge-gray' };
 const MATCH_LABELS = { exact: '정확', name: '이름', alias: '별칭', spec: '규격', chosung: '초성', chosung_alias: '초성' };
 
 let currentPage = 1;