Working with non-lifecycle nodes

[norro]

When the system definition (SMH) contains non-lifecycle nodes, inference will most probably fail, because nodes woll not report any (of the specified) states / transitions used by the inference.

Two options are:

1. Introduce DONT-CARE in the SMH specification for states or
2. (more convenient and flexible), let the mode manager / inference check for all nodes whether they are lifecycle nodes or states/transitions need to be ignored. Check can be done with the get_service_names_and_types_by_node() method.

When working, a launch test with a system consisting of i) rclcpp nodes, ii) rclcpp lifecycle nodes, rcl nodes, and iv) rclpy nodes would be great.