Rely on rosdoc2 for building documentation

### Summary

There is already a ros-distributed tool for generating documentation for ros2 packages. It is [rosdoc2](https://github.com/ros-infrastructure/rosdoc2).

We could benefit from using this tool and solve the documentation generation in a ros way.

Start by reviewing how this repository currently builds its documentation, then compare that process with rosdoc2. Done means the project uses rosdoc2 for documentation generation in a documented, reproducible way.

Written by the indexing model from the issue text.