Improve parameter handling

[azeey]

🦟 Bug fix

Summary

Builds on top of #663 and improves parameter handling so that <param> tags can be used in XML just like how it's used in <node> tags. Previously, the the bridge_params parameter was used and there was some custom parsing in the code. This PR uses code from launch_ros/actions/node.py so we get all the parsing for free.

So to set qos overrides, it would look like

<ros_gz_bridge 
    bridge_name="ros_gz_bridge"
    config_file="$(find-pkg-share ros_gz_sim_demos)/config/air_pressure.yaml"
    use_composition="false">
    
  <param name="qos_overrides./air_pressure.subscription.reliability" value="best_effort" />
</ros_gz_bridge>

Instead of

  <ros_gz_bridge
    bridge_name="ros_gz_bridge"
    config_file="$(find-pkg-share ros_gz_sim_demos)/config/air_pressure.yaml"
    use_composition="true"
    bridge_params="'qos_overrides./air_pressure.publisher.reliability': 'best_effort'" />

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[azeey]

Note that this is a breaking change relative to #628, but I think it's okay since we haven't made a release.

[ahcorde]

https://github.com/Mergifyio backport jazzy

[mergify]

backport jazzy

✅ Backports have been created

• #671 Improve parameter handling (backport #664) has been created for branch jazzy but encountered conflicts