ros2-core

# ROS 2 Jazzy (Ubuntu 24.04 LTS) Core Development Instructions ## 1. Documentation Entry Points Navigate within these rather than guessing deep URLs. | For | Entry point | | :--- | :--- | | Jazzy concepts, tutorials, how-to guides | `https://docs.ros.org/en/jazzy/` | | `rclcpp` C++ API index | `https://docs.ros.org/en/jazzy/p/rclcpp/` | | `rclpy` Python API index | `https://docs.ros.org/en/jazzy/p/rclpy/` | | Robot bringup: TF tree, odometry, EKF fusion | `https://docs.nav2.org/setup_guides/index.html` | ## 2. Symbols to Verify There (never write these from memory) - **TF2** — `tf2_ros::TransformBroadcaster`, `tf2_ros::StaticTransformBroadcaster`, `tf2_ros::Buffer`, `tf2_ros::TransformListener`, `canTransform()`, `lookupTransform()`, `tf2::TimePointZero`, `tf2::ExtrapolationException`; message `geometry_msgs/msg/TransformStamped`. Frame conventions are REP 105 (`map` -> `odom` -> `base_link` -> `base_footprint` -> sensor frames) — see `ros2-troubleshooting`. - **QoS** — `rclcpp::SensorDataQoS()` / `rclpy.qos.qos_profile_sensor_data` on sensor topics; inspect real endpoint QoS with `ros2 topic info <topic> -v`. The depth-only default (`create_subscription(..., 10)`) is RELIABLE + **VOLATILE** — not TRANSIENT_LOCAL; check the enum rather than asserting it. - **Packaging & build wiring** — see `ros2-package`. ## 3. Local System Inspection & Interfaces (Ground Truth) - **Message Definition Inspection**: `ros2 interface show <interface_name>` (e.g. `ros2 interface show nav_m...