Bugfix/move action capability consistent thread

[riv-mjohnson]

Description

Uses a single persistent thread in the move action capability.
Should fix #3691 for move action capabilities.

Update: now includes @riv-jkambites fix to make the persistent thread only use cpu when work is available.

When this is merged, could it be backported to Jazzy and Kilted?

Checklist

• Required by CI: Code is auto formatted using clang-format
• Extend the tutorials / documentation reference
• Document API changes relevant to the user in the MIGRATION.md notes
• Create tests, which fail without this PR reference
• Include a screenshot if changing a GUI
• While waiting for someone to review your request, please help review another open pull request to support the maintainers

[codecov]

Codecov Report

❌ Patch coverage is 0% with 23 lines in your changes missing coverage. Please review.
✅ Project coverage is 0.00%. Comparing base (f1135a4) to head (d33ca72).

Files with missing lines	Patch %	Lines
...rc/default_capabilities/move_action_capability.cpp	0.00%	23 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #3692   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files        539     539           
  Lines      47592   47600    +8     
  Branches    6085    6086    +1     
=====================================
- Misses     47592   47600    +8     

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[riv-mjohnson]

The CI is failing with

    [test_get_cartesian_path_request_features_with_move_group-8] /home/runner/work/moveit2/moveit2/.work/target_ws/src/moveit2/moveit_ros/trajectory_cache/test/features/test_get_cartesian_path_request_features_with_move_group.cpp:105: Failure
    [test_get_cartesian_path_request_features_with_move_group-8] Expected equality of these values:
    [test_get_cartesian_path_request_features_with_move_group-8]   coll.queryList(exact_query).size()
    [test_get_cartesian_path_request_features_with_move_group-8]     Which is: 0
    [test_get_cartesian_path_request_features_with_move_group-8]   1
    [test_get_cartesian_path_request_features_with_move_group-8] Google Test trace:
    [test_get_cartesian_path_request_features_with_move_group-8] /home/runner/work/moveit2/moveit2/.work/target_ws/src/moveit2/moveit_ros/trajectory_cache/test/features/test_get_cartesian_path_request_features_with_move_group.cpp:90: CartesianStartStateJointStateFeatures
    [test_get_cartesian_path_request_features_with_move_group-8] 
    [test_get_cartesian_path_request_features_with_move_group-8] [  FAILED  ] MoveGroupFixture.GetCartesianPathRequestRoundTrip (4501 ms)
    [test_get_cartesian_path_request_features_with_move_group-8] [----------] 1 test from MoveGroupFixture (4501 ms total)
    [test_get_cartesian_path_request_features_with_move_group-8] 
    [test_get_cartesian_path_request_features_with_move_group-8] [----------] Global test environment tear-down
    [test_get_cartesian_path_request_features_with_move_group-8] [==========] 1 test from 1 test suite ran. (4502 ms total)
    [test_get_cartesian_path_request_features_with_move_group-8] [  PASSED  ] 0 tests.
    [test_get_cartesian_path_request_features_with_move_group-8] [  FAILED  ] 1 test, listed below:
    [test_get_cartesian_path_request_features_with_move_group-8] [  FAILED  ] MoveGroupFixture.GetCartesianPathRequestRoundTrip

Is this related to the changes made in this PR, or something which also fails in rolling?