Range Flow-based 2D odometry (ICRA 2016). Provides continuous odom->base_footprint TF from /scan without wheel odometry. Refactored: core algorithm in pure C++ class, ROS coupling only in node wrapper.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
