feat(vacation): 조퇴 연차 차감 처리 (0.75일 = 반차+반반차)

- EARLY_LEAVE vacation type 추가 (deduct_days=0.75)
- work-status: isLeave=true + 동적 vacation_type_id 조회 + 실패 보호
- annual-overview: 월별 요약 테이블에 조퇴 컬럼 추가 + 편집 드롭다운

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

system1-factory/api/db/migrations/20260331_fix_deduct_days_precision.sql

@@ -7,3 +7,6 @@ DELETE svb FROM sp_vacation_balances svb
 JOIN vacation_types vt ON svb.vacation_type_id = vt.id
 WHERE svb.balance_type = 'COMPANY_GRANT'
   AND vt.type_code IN ('CARRYOVER', 'LONG_SERVICE', 'ANNUAL_FULL', 'ANNUAL_HALF', 'ANNUAL_QUARTER');
+-- 조퇴 휴가 유형 추가 (0.75일 = 반차+반반차)
+INSERT IGNORE INTO vacation_types (type_code, type_name, deduct_days, is_active, priority)
+VALUES ('EARLY_LEAVE', '조퇴', 0.75, 1, 10);