feat: extract shared cmake modules into ros2_medkit_cmake package

[bburda]

Pull Request

Summary

Move ROS2MedkitCompat, ROS2MedkitCcache, and ROS2MedkitLinting cmake modules from the top-level cmake/ directory into a proper ament package (ros2_medkit_cmake). This fixes the Jenkins ROS buildfarm failure where isolated Debian package builds could not find the shared modules via relative CMAKE_MODULE_PATH paths.

The new package uses ament's *-extras.cmake hook to auto-add CMAKE_MODULE_PATH after find_package(ros2_medkit_cmake). All 11 consuming packages are migrated from relative path includes to find_package() + <buildtool_depend>.

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Issue

• closes Extract shared cmake modules into ros2_medkit_cmake ament package #294

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Type

• Bug fix
• New feature or tests
• Breaking change
• Documentation only

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Testing

• Clean build from scratch: all 13 packages build successfully, ros2_medkit_cmake resolves first (0.77s)
• Full unit test suite: 1692 tests passed, 0 failures
• Verified installed layout: cmake modules + .clang-tidy correctly placed in share/ros2_medkit_cmake/cmake/
• Verified no stale CMAKE_MODULE_PATH references remain in any CMakeLists.txt

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Checklist

• Breaking changes are clearly described (and announced in docs / changelog if needed)
• Tests were added or updated if needed
• Docs were updated if behavior or public API changed

[Copilot]

Pull request overview

This PR addresses ROS buildfarm/isolated build failures by moving shared CMake modules into a dedicated ros2_medkit_cmake ament package and migrating consuming packages to use find_package(ros2_medkit_cmake). It also updates the plugin system to support a new external graph-provider plugin package (with added PluginContext capabilities and tests/docs).

Changes:

• Introduce ros2_medkit_cmake package to install and expose shared CMake modules via *-extras.cmake.
• Migrate multiple packages from relative CMAKE_MODULE_PATH manipulation to find_package(ros2_medkit_cmake REQUIRED) and add corresponding buildtool_depends.
• Extract/introduce ros2_medkit_graph_provider as an external plugin package and extend PluginContext/gateway plumbing to support entity snapshots, fault listing, and cyclic sampler registration.

Reviewed changes

Copilot reviewed 25 out of 26 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/ros2_medkit_serialization/package.xml	Add ros2_medkit_cmake as a buildtool dependency.
src/ros2_medkit_serialization/CMakeLists.txt	Switch to find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_plugins/ros2_medkit_graph_provider/test/test_graph_provider_plugin.cpp	Update/extend graph provider unit tests and add context stubs.
src/ros2_medkit_plugins/ros2_medkit_graph_provider/src/graph_provider_plugin_exports.cpp	Add plugin export entrypoints for dynamic loading.
src/ros2_medkit_plugins/ros2_medkit_graph_provider/src/graph_provider_plugin.cpp	Update plugin to use new PluginContext APIs and config model.
src/ros2_medkit_plugins/ros2_medkit_graph_provider/package.xml	New plugin package manifest.
src/ros2_medkit_plugins/ros2_medkit_graph_provider/include/ros2_medkit_graph_provider/graph_provider_plugin.hpp	Plugin public header adjustments (context/config changes).
src/ros2_medkit_plugins/ros2_medkit_graph_provider/CMakeLists.txt	Build/install plugin module and add plugin-specific tests.
src/ros2_medkit_integration_tests/test/features/test_graph_provider_plugin.test.py	New integration tests validating dynamic plugin loading and endpoint behavior.
src/ros2_medkit_integration_tests/package.xml	Add ros2_medkit_cmake buildtool dep and graph provider as test dependency.
src/ros2_medkit_integration_tests/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_gateway/test/test_gateway_node.cpp	Remove expectations tied to built-in graph provider behavior.
src/ros2_medkit_gateway/src/plugins/plugin_context.cpp	Implement new PluginContext APIs (snapshot/faults/sampler registration).
src/ros2_medkit_gateway/src/gateway_node.cpp	Stop loading graph provider as built-in; pass sampler registry to plugin context; improve plugin path parameter descriptor.
src/ros2_medkit_gateway/package.xml	Add ros2_medkit_cmake buildtool dep; adjust dependencies.
src/ros2_medkit_gateway/launch/gateway.launch.py	Optionally auto-load graph provider plugin if installed (resolve .so path).
src/ros2_medkit_gateway/include/ros2_medkit_gateway/plugins/plugin_types.hpp	Bump PLUGIN_API_VERSION (ABI/vtable change).
src/ros2_medkit_gateway/include/ros2_medkit_gateway/plugins/plugin_context.hpp	Extend PluginContext interface with snapshot/faults/sampler APIs.
src/ros2_medkit_gateway/config/gateway_params.yaml	Add graph provider plugin params and clarify default plugin list.
src/ros2_medkit_gateway/CMakeLists.txt	Switch to find_package(ros2_medkit_cmake); remove built-in graph provider compilation/tests.
src/ros2_medkit_fault_reporter/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_fault_reporter/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_fault_manager/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_fault_manager/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_discovery_plugins/ros2_medkit_topic_beacon/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_discovery_plugins/ros2_medkit_topic_beacon/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_discovery_plugins/ros2_medkit_param_beacon/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_discovery_plugins/ros2_medkit_param_beacon/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_discovery_plugins/ros2_medkit_linux_introspection/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_discovery_plugins/ros2_medkit_linux_introspection/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_discovery_plugins/ros2_medkit_beacon_common/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_discovery_plugins/ros2_medkit_beacon_common/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_diagnostic_bridge/package.xml	Add ros2_medkit_cmake buildtool dependency.
src/ros2_medkit_diagnostic_bridge/CMakeLists.txt	Use find_package(ros2_medkit_cmake) for shared modules.
src/ros2_medkit_cmake/package.xml	New ament package manifest for shared CMake modules.
src/ros2_medkit_cmake/cmake/ros2_medkit_cmake-extras.cmake	Auto-extend CMAKE_MODULE_PATH after find_package.
src/ros2_medkit_cmake/cmake/ROS2MedkitLinting.cmake	Update .clang-tidy lookup path for installed layout.
src/ros2_medkit_cmake/cmake/ROS2MedkitCompat.cmake	Update usage docs to the new find_package(ros2_medkit_cmake) pattern.
src/ros2_medkit_cmake/cmake/ROS2MedkitCcache.cmake	New shared ccache auto-detection module.
src/ros2_medkit_cmake/CMakeLists.txt	New package build/install rules for shared modules and .clang-tidy.
docs/tutorials/plugin-system.rst	Document new PluginContext APIs and graph provider plugin usage; update API version.

Comments suppressed due to low confidence (1)

src/ros2_medkit_gateway/package.xml:17

• gateway.launch.py imports ament_index_python (get_package_share_directory / get_package_prefix), but package.xml does not declare an exec_depend on ament_index_python. This can cause runtime failures in Debian/isolated installs where the dependency isn’t pulled in indirectly. Please add ament_index_python as an exec_depend (or depend) here.

  <buildtool_depend>ament_cmake</buildtool_depend>
  <buildtool_depend>ros2_medkit_cmake</buildtool_depend>

  <depend>rclcpp</depend>
  <depend>diagnostic_msgs</depend>
  <depend>std_msgs</depend>
  <depend>std_srvs</depend>

[mfaferek93]

lgtm!