test(rtabmap_slam): cover scan transform recovery in native tests

Replace the standalone reproducer with registered C++ GoogleTests for 2D and 3D scan recovery. Use real ROS inputs, separate DDS domains and bounded timeouts, and include rtabmap_slam in supported CI and coverage jobs.

Validated on Jazzy with RTAB-Map core 9ed83a7: both negative controls fail map recovery without the unlocks; both pass with the fix, followed by five repeated runs per case (10/10 passed). Broader distro CI has not been run locally.

rtabmap_slam/package.xml

@@ -35,6 +35,9 @@
   <depend>rtabmap_util</depend>
   <depend>rtabmap_sync</depend>
   
+  <test_depend>ament_cmake_gtest</test_depend>
+  <test_depend>rcl_interfaces</test_depend>
+
   <export>
 	<build_type>ament_cmake</build_type>
   </export>