Feature/ci pipeline

[karakayahuseyin]

This pull request introduces a comprehensive C++ and Python testing framework for the project, integrates it into CI, and adds robust unit tests for core C++ modules. The main highlights are the addition of a GitHub Actions CI workflow, C++ unit test targets and test runner, and improved Python test scripts for dialect parsing and generator validation.

Continuous Integration & Build System Integration

• Added a GitHub Actions workflow (.github/workflows/ci.yml) to automate build, Python and C++ unit tests, and dialect validation on push and pull requests.
• Updated CMake configuration to enable CTest and add a C++ test runner executable (test_runner) that runs all C++ unit tests. [1] [2]

C++ Unit Tests

• Added C++ unit tests for the Router service (bridge/test/test_router.cc) covering subscription, message routing, filter logic, and cleanup.
• Added C++ unit tests for the MessageConverter (bridge/test/test_converter.cc) to verify round-trip conversion between MAVLink and Protobuf messages.
• Created a test runner (bridge/test/test_runner.cc) to orchestrate and report results for all C++ unit tests.

Python Test Improvements

• Improved dialect path detection in Python test scripts (generator/test/test_parser.py, generator/test/test_generator.py) to support both third_party/mavlink and mavlink source directories. [1] [2]
• Updated generator test to use get_flattened_dialect for more robust dialect loading.

Dependency Updates

• Added nlohmann-json3-dev to system dependencies in both the setup script and CI workflow to support C++ JSON functionality. [1] [2]