vehicle: set initial maximum speed tp 100 for powered vehicles

server/src/vehicle/rail/poweredrailvehicle.cpp

@@ -37,6 +37,8 @@ PoweredRailVehicle::PoweredRailVehicle(World& world, std::string_view id_)
 {
   const bool editable = contains(m_world.state.value(), WorldState::Edit);
 
+  speedMax.setValueInternal(100.0);
+
   Attributes::addDisplayName(power, DisplayName::Vehicle::Rail::power);
   Attributes::addEnabled(power, editable);
   m_interfaceItems.add(power);