Deprecate get_status() on action client goal handles in favor of get_status_code()

[dv-picknik]

Description

#3292 adds get_status_code() to ClientGoalHandle and GenericClientGoalHandle. It returns a GoalStatusCode enum and throws InvalidGoalStatusError if the server sent a status outside the action_msgs/GoalStatus values. This issue proposes deprecating get_status(), which returns the raw int8_t, so callers move to the typed getter.

Depends on #3292.

Motivation

Two getters return the same value in different forms. get_status() passes through whatever the server sent. Callers compare it against GoalStatus::STATUS_* constants and have to handle out-of-range values themselves. With one getter, every caller gets the type and the range check.

Design / Implementation Considerations

• Rolling only. A deprecation in a released distro would add warnings there, so this one should not be backported. Add GoalStatusCode enum and get_status_code() to client goal handles #3292 can be.

• It follows the pattern from deprecate rclcpp::spin_some and rclcpp::spin_all #2848: [[deprecated("use get_status_code() instead")]] before RCLCPP_ACTION_PUBLIC, and RCPPUTILS_DEPRECATION_WARNING_OFF_START/STOP around tests that still call get_status().

• I have a branch ready. It moves 39 test assertions and 5 benchmark checks in rclcpp_action to get_status_code(), and rclcpp_action builds without warnings.

• Downstream projects need their own PRs to switch to get_status_code():

  • Nav2 has 5 call sites, including nav2_behavior_tree/bt_action_node.hpp.
  • MoveIt 2 has 1, in the motion planning RViz plugin.

  I found these with GitHub code search on default branches, so the list may be incomplete. Those PRs can merge once get_status_code() is in a rolling release. A branch that also builds for released distros will need a version check, because those distros don't have get_status_code(). I plan to open the PRs for Nav2 and MoveIt 2. Ideally they merge before the deprecation, so neither project sees the warning.

Additional Information

get_status_code() throws where get_status() did not. A caller that reads the status on every tick, like bt_action_node, will need to decide how to handle InvalidGoalStatusError. Checking the status where it arrives, in handle_status_message() and the result callback, would remove that case. That belongs in a separate change.

Done when

• Add GoalStatusCode enum and get_status_code() to client goal handles #3292 is merged and released in rolling.
• Nav2 uses get_status_code().
• MoveIt 2 uses get_status_code().
• get_status() is deprecated on rolling.

Claude Code with Claude Opus 5.5 drafted this issue. I reviewed it.

[jmachowinski]

Note, for this being allowed to be merged, we don't need to track down the compile errors in 'downstream downstream' packages like nav2. We only need to make sure, that a source install of ros2
https://docs.ros.org/en/rolling/Get-Started/Installation/Alternatives/Ubuntu-Development-Setup.html
does not generate any compile warnings due to the deprecation of the API.