feat(tksafety): 위험성평가 모듈 Phase 1 구현 — DB·API·Excel·프론트엔드

5개 테이블(risk_projects/processes/items/mitigations/templates) + 마스터 시딩,
프로젝트·항목·감소대책 CRUD API, ExcelJS 평가표 내보내기,
프로젝트 목록·평가 수행 페이지, 사진 업로드(multer), 네비게이션·CSS 추가.

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

tksafety/web/static/css/tksafety.css

@@ -107,6 +107,17 @@ body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; b
   .visit-table td:last-child { gap: 2px; display: flex; flex-wrap: nowrap; justify-content: flex-end; align-items: center; }
 }
 
+/* Risk assessment */
+.badge-risk-high { background: #fef2f2; color: #dc2626; }
+.badge-risk-substantial { background: #fff7ed; color: #ea580c; }
+.badge-risk-moderate { background: #fefce8; color: #ca8a04; }
+.badge-risk-low { background: #f0fdf4; color: #16a34a; }
+.risk-table th { background: #dc2626; color: white; padding: 0.5rem; font-size: 0.75rem; text-align: center; white-space: nowrap; }
+.risk-table td { padding: 0.5rem; border: 1px solid #e5e7eb; font-size: 0.8rem; vertical-align: middle; }
+.risk-table tr:hover { background: #fef2f2; }
+.risk-section-header { background: #fee2e2; font-weight: 600; }
+.process-caret { transition: transform 0.2s; display: inline-block; }
+
 /* iOS zoom prevention */
 @media (max-width: 768px) {
   input, select, textarea { font-size: 16px !important; }