feat: add centralized error logging system

- Implemented Error Log API to capture and store error logs from various services.
- Updated admin_ui to include Error Log Viewer component for inspecting logs.
- Enhanced error handling in auth_api, employee_api, and transit_api to report errors to the Error Log API.
- Modified existing services to utilize the new error logging functionality.
- Updated Docker Compose configuration to include the Error Log API service.
- Added error logging service in bus_terminal for Flutter application.

admin_ui/src/components/FleetManager.jsx

@@ -9,7 +9,7 @@ export default function FleetManager({ token, user }) {
   const [licensePlate, setLicensePlate] = useState('')
   const [message, setMessage] = useState(null)
   const [canCreateBus, setCanCreateBus] = useState(true)
-  const [isAdmin] = useState(Boolean(user?.userCode))
+  const [isAdmin] = useState(Boolean(user?.isAdmin))
   const [editingBus, setEditingBus] = useState(null)
   const [deleteConfirm, setDeleteConfirm] = useState(null)