feat: 실시간 알림 시스템 (Web Push + 알림 벨 + 서비스간 알림 연동)

- Phase 1: 모든 서비스 헤더에 알림 벨 UI 추가 (notification-bell.js)
- Phase 2: VAPID Web Push 구독/전송 (push-sw.js, pushSubscription API)
- Phase 3: 내부 알림 API + notifyHelper로 서비스간 알림 연동
  - tksafety: 출입 승인/반려, 안전교육 완료, 방문자 체크인
  - tkpurchase: 일용공 신청, 작업보고서 제출
  - system2-report: 신고 접수/확인/처리완료
- Phase 4: 30일 이상 알림 자동 정리 cron, Redis 캐싱
- CORS에 tkuser/tkpurchase/tksafety 서브도메인 추가
- HTML cache busting 버전 갱신

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

docker-compose.yml

@@ -103,6 +103,10 @@ services:
       - REDIS_PORT=6379
       - WEATHER_API_URL=${WEATHER_API_URL:-}
       - WEATHER_API_KEY=${WEATHER_API_KEY:-}
+      - VAPID_PUBLIC_KEY=${VAPID_PUBLIC_KEY}
+      - VAPID_PRIVATE_KEY=${VAPID_PRIVATE_KEY}
+      - VAPID_SUBJECT=${VAPID_SUBJECT:-mailto:admin@technicalkorea.net}
+      - INTERNAL_SERVICE_KEY=${INTERNAL_SERVICE_KEY}
     volumes:
       - system1_uploads:/usr/src/app/uploads
       - system1_logs:/usr/src/app/logs
@@ -172,6 +176,7 @@ services:
       - M_PROJECT_USERNAME=${M_PROJECT_USERNAME:-api_service}
       - M_PROJECT_PASSWORD=${M_PROJECT_PASSWORD:-}
       - M_PROJECT_DEFAULT_PROJECT_ID=${M_PROJECT_DEFAULT_PROJECT_ID:-1}
+      - INTERNAL_SERVICE_KEY=${INTERNAL_SERVICE_KEY}
     volumes:
       - system2_uploads:/usr/src/app/uploads
       - system2_logs:/usr/src/app/logs
@@ -306,6 +311,7 @@ services:
       - DB_PASSWORD=${MYSQL_PASSWORD}
       - DB_NAME=${MYSQL_DATABASE:-hyungi}
       - SSO_JWT_SECRET=${SSO_JWT_SECRET}
+      - INTERNAL_SERVICE_KEY=${INTERNAL_SERVICE_KEY}
     depends_on:
       mariadb:
         condition: service_healthy
@@ -346,6 +352,7 @@ services:
       - DB_PASSWORD=${MYSQL_PASSWORD}
       - DB_NAME=${MYSQL_DATABASE:-hyungi}
       - SSO_JWT_SECRET=${SSO_JWT_SECRET}
+      - INTERNAL_SERVICE_KEY=${INTERNAL_SERVICE_KEY}
     depends_on:
       mariadb:
         condition: service_healthy