feat(cpp_trees): default MANYMOVE_WITH_MEDKIT to OFF

Switch the toggle default so a fresh clone of manymove builds with no
extra deps. Users who want the medkit integration opt in via the env
var (rosdep) plus the CMake arg, mirroring how the Isaac ROS pieces
are handled. README and FAULT_CODES.md document the opt-in flow.

Author: mfaferek93

docs/FAULT_CODES.md

@@ -1,7 +1,10 @@
 # manymove fault codes
 
 This is the catalogue of fault codes emitted by `manymove_cpp_trees` BT action
-nodes via [`ros2_medkit_fault_reporter`](https://github.com/selfpatch/ros2_medkit).
+nodes via [`ros2_medkit_fault_reporter`](https://github.com/selfpatch/ros2_medkit)
+when built with `MANYMOVE_WITH_MEDKIT=ON` (see the package README for the
+build instructions). With the option OFF the same `reportFault()` call sites
+compile to no-ops and nothing is published.
 Each entry below maps to one or more `reportFault()` call sites in the action
 node sources; the source-of-truth string constants live in
 `manymove_cpp_trees/include/manymove_cpp_trees/fault_codes.hpp`.

manymove_cpp_trees/CMakeLists.txt

@@ -14,12 +14,14 @@ endif()
 #--------------------------------------------------------------------
 # Build options
 #--------------------------------------------------------------------
-# ros2_medkit fault reporting is on by default. Turn it off to build
-# without the medkit overlay (action nodes still compile, every
-# reportFault()/reportFaultPassed() call becomes a no-op).
+# ros2_medkit fault reporting is off by default to keep the upstream
+# build free of extra deps. Turn it on (-DMANYMOVE_WITH_MEDKIT=ON plus
+# MANYMOVE_WITH_MEDKIT=1 in the env for rosdep) to pull in the medkit
+# overlay; with it off, the FaultReporting mixin and installFaultReporter()
+# compile to no-ops so action nodes build unchanged.
 option(MANYMOVE_WITH_MEDKIT
   "Build with ros2_medkit fault reporting integration"
-  ON)
+  OFF)
 
 #--------------------------------------------------------------------
 # Dependencies

manymove_cpp_trees/README.md

@@ -42,6 +42,21 @@ Each executable spins the BT factory, registers the custom nodes, and runs the `
 - Control and runtime messaging: `rclcpp`, `rclcpp_action`, `control_msgs`, `std_msgs`, `std_srvs`, `topic_based_ros2_control`
 - Simulation and perception bridges: `simulation_interfaces`, `vision_msgs`
 
+## Optional: ros2_medkit fault reporting
+The package can emit structured fault events via
+[`ros2_medkit`](https://github.com/selfpatch/ros2_medkit) when built with
+`MANYMOVE_WITH_MEDKIT=ON`. With the option OFF (default) the action nodes
+build with no extra dependencies and every `reportFault()` call compiles
+to a no-op. To enable:
+
+```bash
+export MANYMOVE_WITH_MEDKIT=1                                # for rosdep
+rosdep install --from-paths src --ignore-src -y
+colcon build --cmake-args -DMANYMOVE_WITH_MEDKIT=ON          # for the build
+```
+
+See [`docs/FAULT_CODES.md`](../docs/FAULT_CODES.md) for the catalogue.
+
 ## Notes
 - Robot safety mechanisms (stop buttons, workspace supervision) must be handled externally.
 - Review the main README for project-wide disclaimers, contribution guidance, and licensing details.

manymove_cpp_trees/package.xml

@@ -27,13 +27,12 @@
   <depend>simulation_interfaces</depend>
   <depend>vision_msgs</depend>
   <depend>rcpputils</depend>
-  <!-- ros2_medkit deps follow the MANYMOVE_WITH_MEDKIT CMake option. The
-       rosdep condition keys off the env var of the same name: unset or any
-       non-zero value -> install (default), MANYMOVE_WITH_MEDKIT=0 -> skip.
-       This keeps the binary distro install (rosdep + apt) aligned with the
-       compile-time switch in CMakeLists.txt. -->
-  <depend condition="$MANYMOVE_WITH_MEDKIT != 0">ros2_medkit_fault_reporter</depend>
-  <depend condition="$MANYMOVE_WITH_MEDKIT != 0">ros2_medkit_msgs</depend>
+  <!-- ros2_medkit deps follow the MANYMOVE_WITH_MEDKIT CMake option (default
+       OFF). The rosdep condition keys off the env var of the same name:
+       MANYMOVE_WITH_MEDKIT=1 -> install, unset or any other value -> skip.
+       Keep this aligned with the CMake option in CMakeLists.txt. -->
+  <depend condition="$MANYMOVE_WITH_MEDKIT == 1">ros2_medkit_fault_reporter</depend>
+  <depend condition="$MANYMOVE_WITH_MEDKIT == 1">ros2_medkit_msgs</depend>
 
   <test_depend>ament_lint_auto</test_depend>
   <test_depend>ament_lint_common</test_depend>