refactor: worker_id → user_id 전체 마이그레이션 (Phase 1-4)

sso_users.user_id를 단일 식별자로 통합. JWT에서 worker_id 제거,
department_id/is_production 추가. 백엔드 15개 모델, 11개 컨트롤러,
4개 서비스, 7개 라우트, 프론트엔드 32+ JS/11+ HTML 변환.

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

system1-factory/web/pages/attendance/vacation-management.html

@@ -369,7 +369,7 @@
       event.preventDefault();
 
       const data = {
-        worker_id: parseInt(document.getElementById('inputWorker').value),
+        user_id: parseInt(document.getElementById('inputWorker').value),
         vacation_type_id: parseInt(document.getElementById('inputVacationType').value),
         start_date: document.getElementById('inputStartDate').value,
         end_date: document.getElementById('inputEndDate').value,