feat(system-reset): add system reset and factory reset feature

- Add FACTORY_RESET_ON_STARTUP and ENABLE_FACTORY_RESET config settings
- Create app/utils/system_reset.py with core reset logic (wipe DB + files, reimport)
- Create app/api/system_reset.py with admin-only API endpoints
- Create app/views/system_reset.py with admin-only UI view
- Create frontend/templates/system_reset.html with confirmation dialogs
- Auto-reset on startup when FACTORY_RESET_ON_STARTUP=true
- Re-import uses watch folder mechanism for re-ingestion
- Register routers in API and views init files
- Add i18n keys and SETTING_METADATA entries
- Add nav links in base.html (desktop + mobile)

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/api/__init__.py

@@ -43,6 +43,7 @@ from app.api.shared_links import public_router as shared_links_public_router
 from app.api.shared_links import router as shared_links_router
 from app.api.similarity import router as similarity_router
 from app.api.subscriptions import router as subscriptions_router
+from app.api.system_reset import router as system_reset_router
 from app.api.translation import router as translation_router
 from app.api.url_upload import router as url_upload_router
 
@@ -97,4 +98,5 @@ router.include_router(audit_logs_router)
 router.include_router(i18n_router)
 router.include_router(mobile_router)
 router.include_router(compliance_router)
+router.include_router(system_reset_router)
 router.include_router(translation_router)