Add device diagnostics messages

[ipa-vsp]

This pull request introduces the implementation of the diagnostic messages publisher for the diagnostic_msgs/msg/DiagnosticArray.msg message type. The publisher is responsible for publishing device information, including:

• NMT Status
• EMCY Status
• CiA402:
  • Mode switch status
  • Device state of operation.

Reference issue: #104 Depends on: #115

In order to send the device a diagnostic message, an additional timer callback must be added. Therefore by default, the diagnostic publisher is disabled. In order to enable it, add the following to the bus.yml file.

diagnostics:
    enable: true
    period: 1000 # in milliseconds

[or]

diagnostics:
    enable: true

Example: ros2 launch canopen_tests cia402_diagnostics_setup.launch.py

Todo:

• [x] Switch from logging key values to monitor
• [x] Key value structure:
  • Proxy driver:
    • driver_state
    • nmt_state
    • emcy_state
  • CiA402: (Additional)
    • cia402_state
    • cia402_mode
• [x] Update documentation