AP_DDS: Add trajectory tracking control for Plane

[Ryanf55]

Feature request

Is your feature request related to a problem? Please describe.

The external control interface currently supports velocity control in body and earth frame. While #25381 is intended for high-level waypoint control, there is another desired form - trajectory control, that works well for plane.

Describe the solution you'd like

• Design/pick a ROS message for trajectory control, based on mavlink, REP-147, and current research.
• Add the interface for trajectory control in AP_ExternalControl
• Implement the trajectory control in Plane
• Write up a ROS 2 example demonstrating usage on a lemniscate or oval pattern
• Contribute documentation to the wiki on how to run it

Describe alternatives you've considered

Velocity control as a workaround

Platform
[ ] All
[ ] AntennaTracker
[ ] Copter
[ x] Plane
[ ] Rover
[ ] Submarine

Additional context

https://ieeexplore.ieee.org/document/5611328

[Astik-2002]

Hello Ryan. Is someone working on this issue actively? If not, I'd like to work on this issue.

[Astik-2002]

I believe we can already control the position and yaw of a fixed-wing in guided mode. Do we need further inner-loop control with this?

[Ryanf55]

Yea, I thought so too. Did you see this PR?
#26143

[srmainwaring]

These two PRs adapt the L1 nav controller for path guidance in plane:

• Plane: handle guided path requests in GUIDED mode #26328
• DDS: add guided path external control and implement for plane #26339