**UPDATED ENDPOINTS (3 additional):**
- files/list-with-attachments.ts (CRITICAL: was using old auth)
- files/proxy-preview.ts (SECURITY ISSUE: had NO auth)
- files/proxy-download.ts (SECURITY ISSUE: had NO auth)
**AUTHENTICATION:** All now support dual auth:
- x-tag header (webhooks/external calls)
- Keycloak session (logged-in users)
**PROGRESS:** 31/47 endpoints completed (~66%)
**TOTAL UPDATED TODAY:** 14 endpoints
**READY TO CONTINUE:** Remaining 16 endpoints need updating
- Create new `/api/files/proxy-preview` endpoint that fetches and serves files directly
- Update FilePreviewModal to use proxy endpoint for images and PDFs
- Set appropriate headers for inline display and caching
- Remove trailing slash from folder display names in file list