hmon: add C++ interface to heartbeat monitor

[arkjedrz]

Add C++ interface to heartbeat monitor.

Resolves #69

[github-actions]

License Check Results

🚀 The license check job ran with the Bazel command:

bazel run --lockfile_mode=error //:license-check

Status: ⚠️ Needs Review

Click to expand output

[License Check Output]
Extracting Bazel installation...
Starting local Bazel server (8.4.2) and connecting to it...
INFO: Invocation ID: e52ae409-82ab-4fb7-985d-bbd3ed6f4431
Computing main repo mapping: 
Computing main repo mapping: 
Computing main repo mapping: 
WARNING: For repository 'score_rust_policies', the root module requires module version score_rust_policies@0.0.3, but got score_rust_policies@0.0.5 in the resolved dependency graph. Please update the version in your MODULE.bazel or set --check_direct_dependencies=off
Loading: 
Loading: 0 packages loaded
Loading: 0 packages loaded
Loading: 0 packages loaded
    currently loading: 
Loading: 0 packages loaded
    currently loading: 
Loading: 0 packages loaded
    currently loading: 
Loading: 0 packages loaded
    currently loading: 
Analyzing: target //:license-check (1 packages loaded, 0 targets configured)
Analyzing: target //:license-check (1 packages loaded, 0 targets configured)

Analyzing: target //:license-check (38 packages loaded, 9 targets configured)

Analyzing: target //:license-check (89 packages loaded, 9 targets configured)

Analyzing: target //:license-check (145 packages loaded, 1999 targets configured)

Analyzing: target //:license-check (153 packages loaded, 5461 targets configured)

Analyzing: target //:license-check (157 packages loaded, 7842 targets configured)

Analyzing: target //:license-check (165 packages loaded, 7901 targets configured)

Analyzing: target //:license-check (165 packages loaded, 7901 targets configured)

Analyzing: target //:license-check (165 packages loaded, 7901 targets configured)

Analyzing: target //:license-check (168 packages loaded, 9789 targets configured)

Analyzing: target //:license-check (169 packages loaded, 9913 targets configured)

INFO: Analyzed target //:license-check (170 packages loaded, 10039 targets configured).
[7 / 15] Creating runfiles tree bazel-out/k8-opt-exec-ST-d57f47055a04/bin/external/score_tooling+/dash/tool/formatters/dash_format_converter.runfiles [for tool]; 0s local
[13 / 16] JavaToolchainCompileClasses external/rules_java+/toolchains/platformclasspath_classes; 0s disk-cache, processwrapper-sandbox
[14 / 16] JavaToolchainCompileBootClasspath external/rules_java+/toolchains/platformclasspath.jar; 0s disk-cache, processwrapper-sandbox
INFO: Found 1 target...
Target //:license.check.license_check up-to-date:
  bazel-bin/license.check.license_check
  bazel-bin/license.check.license_check.jar
INFO: Elapsed time: 26.369s, Critical Path: 2.68s
INFO: 16 processes: 12 internal, 3 processwrapper-sandbox, 1 worker.
INFO: Build completed successfully, 16 total actions
INFO: Running command line: bazel-bin/license.check.license_check ./formatted.txt <args omitted>
usage: org.eclipse.dash.licenses.cli.Main [-batch <int>] [-cd <url>]
       [-confidence <int>] [-ef <url>] [-excludeSources <sources>] [-help] [-lic
       <url>] [-project <shortname>] [-repo <url>] [-review] [-summary <file>]
       [-timeout <seconds>] [-token <token>]

[github-actions]

The created documentation from the pull request is available at: docu-html

[Copilot]

Pull request overview

This PR adds a new Heartbeat monitor to the health monitoring library and exposes it through the existing C++ API surface (via Rust FFI), integrating it into the HealthMonitor build/start workflow.

Changes:

• Introduces a Rust HeartbeatMonitor (state, evaluation logic, builder) plus FFI exports for C++.
• Extends HealthMonitorBuilder / HealthMonitor to store, retrieve, and start heartbeat monitors alongside deadline monitors.
• Adds C++ wrapper types, wiring in HealthMonitorBuilder::add_heartbeat_monitor / HealthMonitor::get_heartbeat_monitor, and updates C++ tests/build.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/health_monitoring_lib/rust/worker.rs	Passes a shared HMON starting Instant into monitor evaluation and logs heartbeat evaluation errors.
src/health_monitoring_lib/rust/lib.rs	Adds heartbeat monitor storage/build/retrieval and includes heartbeat monitors when starting the worker.
src/health_monitoring_lib/rust/heartbeat/mod.rs	Introduces the heartbeat module exports and FFI submodule.
src/health_monitoring_lib/rust/heartbeat/heartbeat_state.rs	Adds packed atomic heartbeat state representation plus unit tests.
src/health_monitoring_lib/rust/heartbeat/heartbeat_monitor.rs	Implements heartbeat monitor builder, evaluation logic, and tests (incl. loom tests).
src/health_monitoring_lib/rust/heartbeat/ffi.rs	Adds FFI functions for heartbeat builder creation/destruction and sending heartbeats from C++.
src/health_monitoring_lib/rust/ffi.rs	Adds FFI to register heartbeat monitors with the HMON builder and to retrieve heartbeat monitors.
src/health_monitoring_lib/rust/deadline/deadline_monitor.rs	Updates evaluator signature and reuses shared time conversion helper.
src/health_monitoring_lib/rust/common.rs	Extends MonitorEvaluator to include an HMON starting point and adds time helpers used by heartbeat.
src/health_monitoring_lib/cpp/tests/health_monitor_test.cpp	Extends the C++ test to build/get/use a heartbeat monitor.
src/health_monitoring_lib/cpp/include/score/hm/heartbeat/heartbeat_monitor.h	Adds the C++ heartbeat monitor and builder API declarations.
src/health_monitoring_lib/cpp/include/score/hm/health_monitor.h	Adds heartbeat monitor inclusion and retrieval APIs to C++ HMON.
src/health_monitoring_lib/cpp/heartbeat_monitor.cpp	Implements the C++ heartbeat wrapper over Rust FFI calls.
src/health_monitoring_lib/cpp/health_monitor.cpp	Wires heartbeat monitor builder/getter calls through to the Rust FFI.
src/health_monitoring_lib/BUILD	Adds the new C++ heartbeat source/header to the build.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[pawelrutkaq]

Dont review this one before #67 is merged as this is based on it.

[pawelrutkaq]

LGTM