Autonomous Navigation State Machine

[shayaf84]

This branch brings together the key components of our autonomy state machine:

• We define nav_coordinator as an orchestration node to receive a navigation goal, transform them into map frame navigation waypoints, and forwards them to the navigation_to_waypoint action server
• We store recent costmaps into a larger cache_map to extend the rover's effective planning horizon
• We rewrote our A* logic to accept GridMaps instead of OccupancyGrids, giving the planner access to richer traversability data
• We refactored the map's utility methods into a separate package so planning and trajectory_following can use the same behavior.
• We wrote some rudimentary hardware launch files test physical LiDAR

[Hiptostee]

lgtm ! 🌾