POST http://localhost/wordpress/wp-json/reservations/v1/object/2/timetable/reservation
{
    "timetable_id": 2,
    "date": "2025-8-31",
    "email": "test@test",
    "full_name": "Test Test",
    "phone": "123 456 789",
    "reservations": [
        {
            "start_block_idx": 16,
            "num_blocks": 1
        }
    ]
}
HTTP 200