- AdminJS at /admin with auth (admin role only)
- Manage: users, categories, tools, content blocks, settings
- DB tables: settings, categories, tools, content_blocks
- Users table: added role (user/admin) and is_blocked fields
- API: /api/settings, /api/tools, /api/content/:section
- Sidebar: admin link visible only for admin users
- Removed /logs from public routes (now in AdminJS)
- Video converter: fixed ffmpeg codecs for RPi5 (h264_v4l2m2m)
- Dependencies: sequelize, @adminjs/sequelize, mariadb
