- `export.py` : `_load_page_or_404(request, page_id)` — 401 sans session,
404 si `PermissionManager.can_view_page` refuse (les 4 formats d'export)
- `dashboard.py` : helper `_require_page_view` sur `GET /api/pages/{id}/download`
et `GET /api/pages/{id}/file-content`
- +1 test de non-régression → suite **1026/1026**, `ruff check app tests` OK