ue5 7 upgrade

[jonyMarino]

Fixes: #

About

This pull request introduces several improvements and updates across build scripts, documentation, Python client examples, and test code. The most significant changes are enhancements to build system compatibility with Unreal Engine versions 5.2 and 5.7, improved Python client usability, and modernization of test code for better reliability and clarity.

Build system and Unreal Engine compatibility

• Updated the build.cmd script to automatically detect Unreal Engine versions 5.2 and 5.7, select the appropriate MSVC toolset, and provide clearer error handling and messaging for standalone and UE-integrated builds.
• Modified the README.md and Linux development documentation to clarify support for Unreal Engine 5.2 and 5.7, and to emphasize using Unreal's bundled toolchain on Linux instead of system-provided Clang/libc++. [1] [2] [3]

Dependency management improvements

• Updated the CMakeLists.txt to fetch a newer version of nlohmann-json (v3.11.3) with SHA256 hash validation, and added compiler-specific flags for Assimp to avoid warnings-as-errors. Also set ASSIMP_WARNINGS_AS_ERRORS=OFF for more robust builds. [1] [2] [3]

Python client enhancements

• Added a new example script keyboard_control.py for controlling a drone interactively via keyboard inputs, demonstrating API usage and asynchronous control patterns.

Test code modernization

• Refactored the Python test test_hello_drone.py to use more idiomatic async patterns, improved pose change detection with a timeout, and clarified sensor data validation. Variable naming was updated for clarity and test assertions now wait for actual pose updates before validating movement. [1] [2]

Serialization fix

• Improved JsonMsgpack::ToJson() in common_utils.hpp to correctly handle msgpack data by passing a pointer range, ensuring reliable deserialization.

Credits to @Uginchus

How Has This Been Tested?

In 5.2 and 5.7 win and linux.

Screenshots and videos (if appropriate):